<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2025 Workiva-->
<!--r:756b01ca-4115-4573-9f4f-b5242a818003,g:b0db7166-5719-47f2-87d4-bc1b32461552-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.firstwatch.com/role/CONSOLIDATEDSTATEMENTSOFOPERATIONSANDCOMPREHENSIVEINCOME" xlink:type="simple" xlink:href="fwrg-20250629.xsd#CONSOLIDATEDSTATEMENTSOFOPERATIONSANDCOMPREHENSIVEINCOME"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/CONSOLIDATEDSTATEMENTSOFOPERATIONSANDCOMPREHENSIVEINCOME" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_64c82ca3-0628-48c6-9858-3ed72e80bc69" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_StatementTable_64c82ca3-0628-48c6-9858-3ed72e80bc69" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_e4607385-87f9-4aaf-8933-788082e9a843" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_64c82ca3-0628-48c6-9858-3ed72e80bc69" xlink:to="loc_srt_ProductOrServiceAxis_e4607385-87f9-4aaf-8933-788082e9a843" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_e4607385-87f9-4aaf-8933-788082e9a843_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_e4607385-87f9-4aaf-8933-788082e9a843" xlink:to="loc_srt_ProductsAndServicesDomain_e4607385-87f9-4aaf-8933-788082e9a843_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_d9eb36d3-d458-4059-b299-d96898405e69" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_e4607385-87f9-4aaf-8933-788082e9a843" xlink:to="loc_srt_ProductsAndServicesDomain_d9eb36d3-d458-4059-b299-d96898405e69" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FranchisorOwnedOutletMember_ae1ffc62-1c1d-41ec-9726-d9f27283bb32" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FranchisorOwnedOutletMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_d9eb36d3-d458-4059-b299-d96898405e69" xlink:to="loc_us-gaap_FranchisorOwnedOutletMember_ae1ffc62-1c1d-41ec-9726-d9f27283bb32" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FranchiseMember_18bdc4d2-9bb3-491f-b3c4-bbd0793ff560" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FranchiseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_d9eb36d3-d458-4059-b299-d96898405e69" xlink:to="loc_us-gaap_FranchiseMember_18bdc4d2-9bb3-491f-b3c4-bbd0793ff560" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesAbstract_adf94c46-e5a0-44b9-90c0-fd11caa2079b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenuesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_RevenuesAbstract_adf94c46-e5a0-44b9-90c0-fd11caa2079b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_1820e874-3a35-42ff-9173-51d5bfc5a86a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_adf94c46-e5a0-44b9-90c0-fd11caa2079b" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_1820e874-3a35-42ff-9173-51d5bfc5a86a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpensesAbstract_0e26f395-1854-43b0-a2ed-8c4aaadca21f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostsAndExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_CostsAndExpensesAbstract_0e26f395-1854-43b0-a2ed-8c4aaadca21f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_317c411e-5d67-4561-9430-33f1470f7cba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_0e26f395-1854-43b0-a2ed-8c4aaadca21f" xlink:to="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_317c411e-5d67-4561-9430-33f1470f7cba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostDirectMaterial_c653798d-5da0-479d-ba40-8d2b9f0ee0b4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostDirectMaterial"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_317c411e-5d67-4561-9430-33f1470f7cba" xlink:to="loc_us-gaap_CostDirectMaterial_c653798d-5da0-479d-ba40-8d2b9f0ee0b4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostDirectLabor_32369da4-1dca-4c51-87cf-dd1b6dea159a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostDirectLabor"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_317c411e-5d67-4561-9430-33f1470f7cba" xlink:to="loc_us-gaap_CostDirectLabor_32369da4-1dca-4c51-87cf-dd1b6dea159a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCostOfOperatingRevenue_fc836b89-da4b-409e-94e6-7f36f5fce684" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherCostOfOperatingRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_317c411e-5d67-4561-9430-33f1470f7cba" xlink:to="loc_us-gaap_OtherCostOfOperatingRevenue_fc836b89-da4b-409e-94e6-7f36f5fce684" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSoldOverhead_e9b912af-77ae-430e-ac77-c313ea773f7c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServicesSoldOverhead"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_317c411e-5d67-4561-9430-33f1470f7cba" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSoldOverhead_e9b912af-77ae-430e-ac77-c313ea773f7c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreOpeningCosts_8e631c93-3efd-47f2-88a9-6178e6fce14b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreOpeningCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_317c411e-5d67-4561-9430-33f1470f7cba" xlink:to="loc_us-gaap_PreOpeningCosts_8e631c93-3efd-47f2-88a9-6178e6fce14b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_5c50f085-3e15-4380-918e-3ade2d08ccb1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_0e26f395-1854-43b0-a2ed-8c4aaadca21f" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_5c50f085-3e15-4380-918e-3ade2d08ccb1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_e29b29b9-1116-4ecb-a084-cca1c77fdaac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_0e26f395-1854-43b0-a2ed-8c4aaadca21f" xlink:to="loc_us-gaap_DepreciationAndAmortization_e29b29b9-1116-4ecb-a084-cca1c77fdaac" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges_a7b7d40a-78f0-4fb0-9b70-c18ffc1136b2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_0e26f395-1854-43b0-a2ed-8c4aaadca21f" xlink:to="loc_us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges_a7b7d40a-78f0-4fb0-9b70-c18ffc1136b2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_TransactionIncomeExpenseNet_e1cc0a5f-bd8f-4d30-8807-0f864d8dc4c3" xlink:href="fwrg-20250629.xsd#fwrg_TransactionIncomeExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_0e26f395-1854-43b0-a2ed-8c4aaadca21f" xlink:to="loc_fwrg_TransactionIncomeExpenseNet_e1cc0a5f-bd8f-4d30-8807-0f864d8dc4c3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpenses_97f9637f-8ad1-446a-b35c-b6546a66a89c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostsAndExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_0e26f395-1854-43b0-a2ed-8c4aaadca21f" xlink:to="loc_us-gaap_CostsAndExpenses_97f9637f-8ad1-446a-b35c-b6546a66a89c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_06731eba-7991-410b-81b6-fbf19ca2bee1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_OperatingIncomeLoss_06731eba-7991-410b-81b6-fbf19ca2bee1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_93f101a2-97fd-4238-8af2-2f3c8ad1a374" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_InterestExpenseNonoperating_93f101a2-97fd-4238-8af2-2f3c8ad1a374" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_ee84d607-7a76-44db-9b47-9eb8554be79c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_NonoperatingIncomeExpense_ee84d607-7a76-44db-9b47-9eb8554be79c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_cc7b273c-b245-4889-a50c-805751cb595a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_cc7b273c-b245-4889-a50c-805751cb595a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_3ba9653c-ac95-486e-8778-0bfedfb92666" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_3ba9653c-ac95-486e-8778-0bfedfb92666" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_b4ad0e07-463b-465b-956d-35890c26d9fd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_NetIncomeLoss_b4ad0e07-463b-465b-956d-35890c26d9fd" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_2bab831f-79c2-45d7-ae4c-85e6bfde5ff6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_3ed72a9b-1c1e-4fd5-b85d-c46ab78ef747" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_3ed72a9b-1c1e-4fd5-b85d-c46ab78ef747" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent_076d0cfa-af49-4cab-b6fa-67538981e9b2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_3ed72a9b-1c1e-4fd5-b85d-c46ab78ef747" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent_076d0cfa-af49-4cab-b6fa-67538981e9b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossTax_e1c0221f-03f0-486e-8a6e-f435159c006b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_3ed72a9b-1c1e-4fd5-b85d-c46ab78ef747" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossTax_e1c0221f-03f0-486e-8a6e-f435159c006b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_924277ec-93d3-49d7-9231-6553f50cae7d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTax_924277ec-93d3-49d7-9231-6553f50cae7d" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_db15965a-aa05-4dc1-ba76-03ebbe8ba7ef" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_EarningsPerShareBasic_db15965a-aa05-4dc1-ba76-03ebbe8ba7ef" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_90467ada-8d19-4293-be26-c7858f7b8166" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_EarningsPerShareDiluted_90467ada-8d19-4293-be26-c7858f7b8166" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_10219857-b397-4f36-9679-634b06fb542d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_10219857-b397-4f36-9679-634b06fb542d" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_556bf858-e4bd-4c71-86ea-692561413871" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_7725d04d-a7e8-4b33-beaa-be0ba2cc70fb" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_556bf858-e4bd-4c71-86ea-692561413871" xlink:type="arc" order="14"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/CONSOLIDATEDSTATEMENTSOFEQUITY" xlink:type="simple" xlink:href="fwrg-20250629.xsd#CONSOLIDATEDSTATEMENTSOFEQUITY"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/CONSOLIDATEDSTATEMENTSOFEQUITY" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_235cb3f7-445d-4f70-a020-a7d53b4349da" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_5ae5ad3b-7a95-4658-ab45-d7d49fb544fb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_235cb3f7-445d-4f70-a020-a7d53b4349da" xlink:to="loc_us-gaap_StatementTable_5ae5ad3b-7a95-4658-ab45-d7d49fb544fb" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_55aed6f5-9cdb-4f3f-a85e-35d13d47e811" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_5ae5ad3b-7a95-4658-ab45-d7d49fb544fb" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_55aed6f5-9cdb-4f3f-a85e-35d13d47e811" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_55aed6f5-9cdb-4f3f-a85e-35d13d47e811_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_55aed6f5-9cdb-4f3f-a85e-35d13d47e811" xlink:to="loc_us-gaap_EquityComponentDomain_55aed6f5-9cdb-4f3f-a85e-35d13d47e811_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_d0af5e60-36be-4c7a-baf9-2d8453c835e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_55aed6f5-9cdb-4f3f-a85e-35d13d47e811" xlink:to="loc_us-gaap_EquityComponentDomain_d0af5e60-36be-4c7a-baf9-2d8453c835e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_4ee46991-94f8-44f1-9a03-78e9f97b9483" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_d0af5e60-36be-4c7a-baf9-2d8453c835e7" xlink:to="loc_us-gaap_CommonStockMember_4ee46991-94f8-44f1-9a03-78e9f97b9483" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_aa210799-ced1-493a-a716-7081068d1f6e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_d0af5e60-36be-4c7a-baf9-2d8453c835e7" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_aa210799-ced1-493a-a716-7081068d1f6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_12790a13-95b3-4699-936b-ad1e5785d4b1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_d0af5e60-36be-4c7a-baf9-2d8453c835e7" xlink:to="loc_us-gaap_RetainedEarningsMember_12790a13-95b3-4699-936b-ad1e5785d4b1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_2d2f4778-f1f2-450c-82be-b2344770d313" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_d0af5e60-36be-4c7a-baf9-2d8453c835e7" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_2d2f4778-f1f2-450c-82be-b2344770d313" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_10d19e92-68d6-4f44-998e-c034491de261" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_235cb3f7-445d-4f70-a020-a7d53b4349da" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_10d19e92-68d6-4f44-998e-c034491de261" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_4f9a8561-8b08-4b9c-9858-2564e4cbc88f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_10d19e92-68d6-4f44-998e-c034491de261" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_4f9a8561-8b08-4b9c-9858-2564e4cbc88f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_2a5b71b8-0575-4e43-9f80-5a4013a5cbdc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_10d19e92-68d6-4f44-998e-c034491de261" xlink:to="loc_us-gaap_StockholdersEquity_2a5b71b8-0575-4e43-9f80-5a4013a5cbdc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_feb059b4-78dd-420e-83ce-f4dc65bda655" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_10d19e92-68d6-4f44-998e-c034491de261" xlink:to="loc_us-gaap_NetIncomeLoss_feb059b4-78dd-420e-83ce-f4dc65bda655" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_ff298bc8-7c40-4203-ab27-c8ca0a89edc3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_10d19e92-68d6-4f44-998e-c034491de261" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_ff298bc8-7c40-4203-ab27-c8ca0a89edc3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_4fb61399-e243-468d-b4f6-3f93be814633" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_10d19e92-68d6-4f44-998e-c034491de261" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_4fb61399-e243-468d-b4f6-3f93be814633" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_d3ad80b6-e9f3-4e9a-8861-bc8d45f855fd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_10d19e92-68d6-4f44-998e-c034491de261" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_d3ad80b6-e9f3-4e9a-8861-bc8d45f855fd" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_a2de30a5-9fa1-4c8a-8d88-d126986e21d4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_10d19e92-68d6-4f44-998e-c034491de261" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_a2de30a5-9fa1-4c8a-8d88-d126986e21d4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_f61ddbf8-c3c6-42da-9f9e-f1605c082e91" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_971ef2c9-b168-44e8-97b3-91b0e338f8d0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSParenthetical" xlink:type="simple" xlink:href="fwrg-20250629.xsd#CONSOLIDATEDSTATEMENTSOFCASHFLOWSParenthetical"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_b6446eb6-6193-4a88-a0cc-47bf003b2b04" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_4e9bb5f2-340a-4322-8b1e-7441cb84f963" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_b6446eb6-6193-4a88-a0cc-47bf003b2b04" xlink:to="loc_us-gaap_StatementTable_4e9bb5f2-340a-4322-8b1e-7441cb84f963" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_993d37c7-e72b-4c86-ae8a-1ec8611668ef" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_4e9bb5f2-340a-4322-8b1e-7441cb84f963" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_993d37c7-e72b-4c86-ae8a-1ec8611668ef" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_993d37c7-e72b-4c86-ae8a-1ec8611668ef_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_993d37c7-e72b-4c86-ae8a-1ec8611668ef" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_993d37c7-e72b-4c86-ae8a-1ec8611668ef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_19b7a703-b77a-4ed1-9f60-fdc201d86f2b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_993d37c7-e72b-4c86-ae8a-1ec8611668ef" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_19b7a703-b77a-4ed1-9f60-fdc201d86f2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember_f533f90c-6ca0-45ab-8551-d90d91c4ec21" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_19b7a703-b77a-4ed1-9f60-fdc201d86f2b" xlink:to="loc_us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember_f533f90c-6ca0-45ab-8551-d90d91c4ec21" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_932f05e7-03c0-4851-8af6-431736b96ce9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_b6446eb6-6193-4a88-a0cc-47bf003b2b04" xlink:to="loc_us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_932f05e7-03c0-4851-8af6-431736b96ce9" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/NatureofBusinessandOrganizationAdditionalInformationDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#NatureofBusinessandOrganizationAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/NatureofBusinessandOrganizationAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FranchisorDisclosureLineItems_78eb7063-cea2-4436-90fb-35c2b84e8866" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FranchisorDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFranchisorDisclosureTable_31853086-00c0-4bf1-85a2-f28d5a3dc828" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFranchisorDisclosureTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FranchisorDisclosureLineItems_78eb7063-cea2-4436-90fb-35c2b84e8866" xlink:to="loc_us-gaap_ScheduleOfFranchisorDisclosureTable_31853086-00c0-4bf1-85a2-f28d5a3dc828" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FranchisorDisclosureAxis_d5116e9c-511c-4c7a-8580-0cccbb3e6b28" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FranchisorDisclosureAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFranchisorDisclosureTable_31853086-00c0-4bf1-85a2-f28d5a3dc828" xlink:to="loc_us-gaap_FranchisorDisclosureAxis_d5116e9c-511c-4c7a-8580-0cccbb3e6b28" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FranchisorDisclosureDomain_d5116e9c-511c-4c7a-8580-0cccbb3e6b28_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FranchisorDisclosureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FranchisorDisclosureAxis_d5116e9c-511c-4c7a-8580-0cccbb3e6b28" xlink:to="loc_us-gaap_FranchisorDisclosureDomain_d5116e9c-511c-4c7a-8580-0cccbb3e6b28_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FranchisorDisclosureDomain_6f4b32a2-3fe7-4cb5-845d-25ff84f43610" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FranchisorDisclosureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FranchisorDisclosureAxis_d5116e9c-511c-4c7a-8580-0cccbb3e6b28" xlink:to="loc_us-gaap_FranchisorDisclosureDomain_6f4b32a2-3fe7-4cb5-845d-25ff84f43610" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EntityOperatedUnitsMember_ecb22daa-277f-4dad-a95d-4cf5f83c7734" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EntityOperatedUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FranchisorDisclosureDomain_6f4b32a2-3fe7-4cb5-845d-25ff84f43610" xlink:to="loc_us-gaap_EntityOperatedUnitsMember_ecb22daa-277f-4dad-a95d-4cf5f83c7734" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FranchisedUnitsMember_570acb64-1e29-4ace-bbf3-7998988131a6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FranchisedUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FranchisorDisclosureDomain_6f4b32a2-3fe7-4cb5-845d-25ff84f43610" xlink:to="loc_us-gaap_FranchisedUnitsMember_570acb64-1e29-4ace-bbf3-7998988131a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfStatesInWhichEntityOperates_d1244202-77c6-4303-9aee-452c75267caa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfStatesInWhichEntityOperates"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FranchisorDisclosureLineItems_78eb7063-cea2-4436-90fb-35c2b84e8866" xlink:to="loc_us-gaap_NumberOfStatesInWhichEntityOperates_d1244202-77c6-4303-9aee-452c75267caa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRestaurants_85e85472-0a2b-4522-8fe3-0c0e827ac7fd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfRestaurants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FranchisorDisclosureLineItems_78eb7063-cea2-4436-90fb-35c2b84e8866" xlink:to="loc_us-gaap_NumberOfRestaurants_85e85472-0a2b-4522-8fe3-0c0e827ac7fd" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/BusinessAcquisitionsNarrativeDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#BusinessAcquisitionsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/BusinessAcquisitionsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_9cd45292-09ea-479e-9ea9-68dabee9dded" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_a5d54843-36d7-41dd-8756-78b5713d45ed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_9cd45292-09ea-479e-9ea9-68dabee9dded" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_a5d54843-36d7-41dd-8756-78b5713d45ed" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_98ec44b9-e706-422b-92b3-d19cbab284f9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_a5d54843-36d7-41dd-8756-78b5713d45ed" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_98ec44b9-e706-422b-92b3-d19cbab284f9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_98ec44b9-e706-422b-92b3-d19cbab284f9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_98ec44b9-e706-422b-92b3-d19cbab284f9" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_98ec44b9-e706-422b-92b3-d19cbab284f9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_7de4235d-4fc4-4d20-bdca-1cc2ff9e8c9d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_98ec44b9-e706-422b-92b3-d19cbab284f9" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_7de4235d-4fc4-4d20-bdca-1cc2ff9e8c9d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember_a65259db-d742-4813-9cb0-1f6543bc4182" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_7de4235d-4fc4-4d20-bdca-1cc2ff9e8c9d" xlink:to="loc_us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember_a65259db-d742-4813-9cb0-1f6543bc4182" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_NumberOfBusinessAcquisitionTransactions_61e69822-175e-459d-95c1-b8d5f72fa085" xlink:href="fwrg-20250629.xsd#fwrg_NumberOfBusinessAcquisitionTransactions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_9cd45292-09ea-479e-9ea9-68dabee9dded" xlink:to="loc_fwrg_NumberOfBusinessAcquisitionTransactions_61e69822-175e-459d-95c1-b8d5f72fa085" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfBusinessesAcquired_5760ebad-76b7-4d3c-8dae-3b3024bab8b3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfBusinessesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_9cd45292-09ea-479e-9ea9-68dabee9dded" xlink:to="loc_us-gaap_NumberOfBusinessesAcquired_5760ebad-76b7-4d3c-8dae-3b3024bab8b3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_05010eeb-f464-451d-b3b4-553fc359e09a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_9cd45292-09ea-479e-9ea9-68dabee9dded" xlink:to="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_05010eeb-f464-451d-b3b4-553fc359e09a" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/BusinessAcquisitionsScheduleofBusinessAcquisitionsbyAcquisitionDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#BusinessAcquisitionsScheduleofBusinessAcquisitionsbyAcquisitionDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/BusinessAcquisitionsScheduleofBusinessAcquisitionsbyAcquisitionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_106de2f3-e910-47d0-8104-f9bd8300cb02" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_9ae57456-72a5-4516-a44a-972e5e418708" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_106de2f3-e910-47d0-8104-f9bd8300cb02" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_9ae57456-72a5-4516-a44a-972e5e418708" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_2048f4cd-2610-4b5b-bd3a-039c0391bc6e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_9ae57456-72a5-4516-a44a-972e5e418708" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_2048f4cd-2610-4b5b-bd3a-039c0391bc6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2048f4cd-2610-4b5b-bd3a-039c0391bc6e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_2048f4cd-2610-4b5b-bd3a-039c0391bc6e" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_2048f4cd-2610-4b5b-bd3a-039c0391bc6e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_95768e81-9f65-4810-a6b2-ef44a435a54d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_2048f4cd-2610-4b5b-bd3a-039c0391bc6e" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_95768e81-9f65-4810-a6b2-ef44a435a54d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember_36f354cf-27d0-4ac3-87a9-9f67da9e461a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_95768e81-9f65-4810-a6b2-ef44a435a54d" xlink:to="loc_us-gaap_SeriesOfIndividuallyImmaterialBusinessAcquisitionsMember_36f354cf-27d0-4ac3-87a9-9f67da9e461a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfBusinessesAcquired_a04020d1-370b-4711-8055-cef1be10deb5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfBusinessesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_106de2f3-e910-47d0-8104-f9bd8300cb02" xlink:to="loc_us-gaap_NumberOfBusinessesAcquired_a04020d1-370b-4711-8055-cef1be10deb5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_5bb0be02-70d5-4bea-80d5-3de4a192b3a5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireBusinessesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_106de2f3-e910-47d0-8104-f9bd8300cb02" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_5bb0be02-70d5-4bea-80d5-3de4a192b3a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts_4a56313a-7ef5-4ccc-9366-2214d7109b7e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_106de2f3-e910-47d0-8104-f9bd8300cb02" xlink:to="loc_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts_4a56313a-7ef5-4ccc-9366-2214d7109b7e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_ContractWithCustomerLiabilityFranchiseFeeRevenueRevenueRecognizedBusinessCombination_d4a463fc-8077-4f98-b15d-916808a30cce" xlink:href="fwrg-20250629.xsd#fwrg_ContractWithCustomerLiabilityFranchiseFeeRevenueRevenueRecognizedBusinessCombination"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_106de2f3-e910-47d0-8104-f9bd8300cb02" xlink:to="loc_fwrg_ContractWithCustomerLiabilityFranchiseFeeRevenueRevenueRecognizedBusinessCombination_d4a463fc-8077-4f98-b15d-916808a30cce" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_106de2f3-e910-47d0-8104-f9bd8300cb02" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_1955cdfc-dedf-4347-bd5e-8729d59be02f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_1955cdfc-dedf-4347-bd5e-8729d59be02f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_c9461f93-b2bb-461f-ada6-215a336b452a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_c9461f93-b2bb-461f-ada6-215a336b452a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther_49d8d276-f804-43a5-92ec-c98b42640da0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther_49d8d276-f804-43a5-92ec-c98b42640da0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_79aca2f3-3ac8-4d75-ab70-b22520c35343" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_79aca2f3-3ac8-4d75-ab70-b22520c35343" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_cc824a2a-f713-4d7c-aa07-0e518c8f7428" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_cc824a2a-f713-4d7c-aa07-0e518c8f7428" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_e4c10655-acbe-4c8f-8f39-da3ba2a13528" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:to="loc_us-gaap_Goodwill_e4c10655-acbe-4c8f-8f39-da3ba2a13528" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingRightOfUseAssetNetOfLeasePositionAndPrepaidRent_da28fa73-07f9-4a9a-a0a8-a5543ad3ad76" xlink:href="fwrg-20250629.xsd#fwrg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingRightOfUseAssetNetOfLeasePositionAndPrepaidRent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:to="loc_fwrg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingRightOfUseAssetNetOfLeasePositionAndPrepaidRent_da28fa73-07f9-4a9a-a0a8-a5543ad3ad76" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation_5a902d7c-3977-4d60-b6c8-594b5bedb884" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation_5a902d7c-3977-4d60-b6c8-594b5bedb884" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_92781a86-6390-4163-af8b-7c27377328f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_92781a86-6390-4163-af8b-7c27377328f8" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue_e3f309b5-4cfc-410c-bb7e-a27c0fbe4dcb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract_52d27222-33e0-426d-abf3-d2e38763c020" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue_e3f309b5-4cfc-410c-bb7e-a27c0fbe4dcb" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/RevenuesDisaggregationofRevenueDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#RevenuesDisaggregationofRevenueDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/RevenuesDisaggregationofRevenueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_8550de7d-6842-444d-9f04-730d9a772a53" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_b05caec8-2122-467e-b339-16722021dee3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_8550de7d-6842-444d-9f04-730d9a772a53" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_b05caec8-2122-467e-b339-16722021dee3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_4c388d1d-1b4f-4633-97e1-2285ef37e782" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_b05caec8-2122-467e-b339-16722021dee3" xlink:to="loc_srt_ProductOrServiceAxis_4c388d1d-1b4f-4633-97e1-2285ef37e782" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_4c388d1d-1b4f-4633-97e1-2285ef37e782_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_4c388d1d-1b4f-4633-97e1-2285ef37e782" xlink:to="loc_srt_ProductsAndServicesDomain_4c388d1d-1b4f-4633-97e1-2285ef37e782_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_d9a103a2-174e-4112-b3dc-3bc9704be345" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_4c388d1d-1b4f-4633-97e1-2285ef37e782" xlink:to="loc_srt_ProductsAndServicesDomain_d9a103a2-174e-4112-b3dc-3bc9704be345" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FranchisorOwnedOutletMember_75b60794-d2ef-4a4e-bb9e-c38b461415e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FranchisorOwnedOutletMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_d9a103a2-174e-4112-b3dc-3bc9704be345" xlink:to="loc_us-gaap_FranchisorOwnedOutletMember_75b60794-d2ef-4a4e-bb9e-c38b461415e8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_InRestaurantDiningSalesMember_c202188b-841e-41f7-8901-99f3993dd83e" xlink:href="fwrg-20250629.xsd#fwrg_InRestaurantDiningSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FranchisorOwnedOutletMember_75b60794-d2ef-4a4e-bb9e-c38b461415e8" xlink:to="loc_fwrg_InRestaurantDiningSalesMember_c202188b-841e-41f7-8901-99f3993dd83e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_ThirdPartyDeliverySalesMember_37b1e47a-27e5-421f-8eff-da474df9052b" xlink:href="fwrg-20250629.xsd#fwrg_ThirdPartyDeliverySalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FranchisorOwnedOutletMember_75b60794-d2ef-4a4e-bb9e-c38b461415e8" xlink:to="loc_fwrg_ThirdPartyDeliverySalesMember_37b1e47a-27e5-421f-8eff-da474df9052b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_TakeOutSalesMember_d90b7acd-10a6-41fd-b152-c689273ef805" xlink:href="fwrg-20250629.xsd#fwrg_TakeOutSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FranchisorOwnedOutletMember_75b60794-d2ef-4a4e-bb9e-c38b461415e8" xlink:to="loc_fwrg_TakeOutSalesMember_d90b7acd-10a6-41fd-b152-c689273ef805" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FranchiseMember_f13c0f07-ad0a-4a43-affd-f5ad66723731" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FranchiseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_d9a103a2-174e-4112-b3dc-3bc9704be345" xlink:to="loc_us-gaap_FranchiseMember_f13c0f07-ad0a-4a43-affd-f5ad66723731" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_RoyaltyAndSystemFundContributionsMember_3726bfcc-cb69-499e-9abf-8ee079927ef7" xlink:href="fwrg-20250629.xsd#fwrg_RoyaltyAndSystemFundContributionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FranchiseMember_f13c0f07-ad0a-4a43-affd-f5ad66723731" xlink:to="loc_fwrg_RoyaltyAndSystemFundContributionsMember_3726bfcc-cb69-499e-9abf-8ee079927ef7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_InitialFeesMember_985d8bb3-ee76-49ca-8f05-b9f218fb1403" xlink:href="fwrg-20250629.xsd#fwrg_InitialFeesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FranchiseMember_f13c0f07-ad0a-4a43-affd-f5ad66723731" xlink:to="loc_fwrg_InitialFeesMember_985d8bb3-ee76-49ca-8f05-b9f218fb1403" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_BusinessCombinationsRevenuesRecognizedMember_76603ceb-9ba7-4641-8399-c710a61ca0c9" xlink:href="fwrg-20250629.xsd#fwrg_BusinessCombinationsRevenuesRecognizedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FranchiseMember_f13c0f07-ad0a-4a43-affd-f5ad66723731" xlink:to="loc_fwrg_BusinessCombinationsRevenuesRecognizedMember_76603ceb-9ba7-4641-8399-c710a61ca0c9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_aad9122d-d8cc-4cf5-a913-a4f89fa30e1e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_8550de7d-6842-444d-9f04-730d9a772a53" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_aad9122d-d8cc-4cf5-a913-a4f89fa30e1e" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/DebtLongTermDebtNetDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#DebtLongTermDebtNetDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/DebtLongTermDebtNetDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_6c3690a3-8d84-46ad-b5ce-09b0bba4a396" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_1dcbbb30-73aa-4a47-89a1-386f8c842f06" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6c3690a3-8d84-46ad-b5ce-09b0bba4a396" xlink:to="loc_us-gaap_DebtInstrumentTable_1dcbbb30-73aa-4a47-89a1-386f8c842f06" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_e5a0c43d-c9f6-446c-b287-b40c5d69c411" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_1dcbbb30-73aa-4a47-89a1-386f8c842f06" xlink:to="loc_us-gaap_CreditFacilityAxis_e5a0c43d-c9f6-446c-b287-b40c5d69c411" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_e5a0c43d-c9f6-446c-b287-b40c5d69c411_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_e5a0c43d-c9f6-446c-b287-b40c5d69c411" xlink:to="loc_us-gaap_CreditFacilityDomain_e5a0c43d-c9f6-446c-b287-b40c5d69c411_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_4961442b-0067-4c38-ac0e-35862e43577f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_e5a0c43d-c9f6-446c-b287-b40c5d69c411" xlink:to="loc_us-gaap_CreditFacilityDomain_4961442b-0067-4c38-ac0e-35862e43577f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_TermFacilityMember_e219017a-3a10-4d5f-8ffd-1be1cc29b06c" xlink:href="fwrg-20250629.xsd#fwrg_TermFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_4961442b-0067-4c38-ac0e-35862e43577f" xlink:to="loc_fwrg_TermFacilityMember_e219017a-3a10-4d5f-8ffd-1be1cc29b06c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_84aa16c1-8bf9-4bfd-a1aa-f8b3fd042ca0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_4961442b-0067-4c38-ac0e-35862e43577f" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_84aa16c1-8bf9-4bfd-a1aa-f8b3fd042ca0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_21543a56-1029-4668-8d17-237254025d1e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_1dcbbb30-73aa-4a47-89a1-386f8c842f06" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_21543a56-1029-4668-8d17-237254025d1e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_21543a56-1029-4668-8d17-237254025d1e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_21543a56-1029-4668-8d17-237254025d1e" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_21543a56-1029-4668-8d17-237254025d1e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_9765a733-3673-492f-85c0-81222f64eef7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_21543a56-1029-4668-8d17-237254025d1e" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_9765a733-3673-492f-85c0-81222f64eef7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_9ff3cda0-8999-4f4b-8009-0ee2801f38e6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_9765a733-3673-492f-85c0-81222f64eef7" xlink:to="loc_us-gaap_LineOfCreditMember_9ff3cda0-8999-4f4b-8009-0ee2801f38e6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_OtherDebtMember_da4696b3-e1c1-4a41-b118-9593ee5719c3" xlink:href="fwrg-20250629.xsd#fwrg_OtherDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_9765a733-3673-492f-85c0-81222f64eef7" xlink:to="loc_fwrg_OtherDebtMember_da4696b3-e1c1-4a41-b118-9593ee5719c3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_bed04528-593a-4486-8e4e-1532a4ff7bb9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_1dcbbb30-73aa-4a47-89a1-386f8c842f06" xlink:to="loc_us-gaap_DebtInstrumentAxis_bed04528-593a-4486-8e4e-1532a4ff7bb9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_bed04528-593a-4486-8e4e-1532a4ff7bb9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_bed04528-593a-4486-8e4e-1532a4ff7bb9" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_bed04528-593a-4486-8e4e-1532a4ff7bb9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_97382b17-007f-465d-b0d5-116b4b2de2f6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_bed04528-593a-4486-8e4e-1532a4ff7bb9" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_97382b17-007f-465d-b0d5-116b4b2de2f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_NewFacilitiesMember_9aa33e92-6fb1-42c1-98fd-b5e7cf85786c" xlink:href="fwrg-20250629.xsd#fwrg_NewFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_97382b17-007f-465d-b0d5-116b4b2de2f6" xlink:to="loc_fwrg_NewFacilitiesMember_9aa33e92-6fb1-42c1-98fd-b5e7cf85786c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_FinancingObligationsMember_050f6197-6d02-411f-bd6b-b1914608805b" xlink:href="fwrg-20250629.xsd#fwrg_FinancingObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_97382b17-007f-465d-b0d5-116b4b2de2f6" xlink:to="loc_fwrg_FinancingObligationsMember_050f6197-6d02-411f-bd6b-b1914608805b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_16bdc8eb-eeb1-47ee-a238-ee4d1ace89f3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6c3690a3-8d84-46ad-b5ce-09b0bba4a396" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_16bdc8eb-eeb1-47ee-a238-ee4d1ace89f3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_18985614-202a-4fdd-ae28-5b149beb5ac2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6c3690a3-8d84-46ad-b5ce-09b0bba4a396" xlink:to="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_18985614-202a-4fdd-ae28-5b149beb5ac2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiability_917d54de-14fc-4f5b-b9d8-f026011ca281" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinanceLeaseLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6c3690a3-8d84-46ad-b5ce-09b0bba4a396" xlink:to="loc_us-gaap_FinanceLeaseLiability_917d54de-14fc-4f5b-b9d8-f026011ca281" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_b6a2fe61-060d-4042-b334-bde176eff765" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6c3690a3-8d84-46ad-b5ce-09b0bba4a396" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_b6a2fe61-060d-4042-b334-bde176eff765" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndCapitalLeaseObligations_55c3396f-2260-444c-88ca-a942b0123b22" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtAndCapitalLeaseObligations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6c3690a3-8d84-46ad-b5ce-09b0bba4a396" xlink:to="loc_us-gaap_DebtAndCapitalLeaseObligations_55c3396f-2260-444c-88ca-a942b0123b22" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_57746ee9-b589-48e3-af62-8a5a6eeb4974" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6c3690a3-8d84-46ad-b5ce-09b0bba4a396" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_57746ee9-b589-48e3-af62-8a5a6eeb4974" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_f04473f7-48c5-4173-a66b-4d470b1aa931" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_6c3690a3-8d84-46ad-b5ce-09b0bba4a396" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_f04473f7-48c5-4173-a66b-4d470b1aa931" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/DebtNarrativeDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#DebtNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/DebtNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_5fe06321-38fc-4202-bb73-a498e056c0f0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_c0c44d62-7997-4cb8-82e5-87b47d056d48" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5fe06321-38fc-4202-bb73-a498e056c0f0" xlink:to="loc_us-gaap_DebtInstrumentTable_c0c44d62-7997-4cb8-82e5-87b47d056d48" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_6e08aecd-09de-444c-8f06-d3d4d30cb0eb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_c0c44d62-7997-4cb8-82e5-87b47d056d48" xlink:to="loc_us-gaap_CreditFacilityAxis_6e08aecd-09de-444c-8f06-d3d4d30cb0eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_6e08aecd-09de-444c-8f06-d3d4d30cb0eb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_6e08aecd-09de-444c-8f06-d3d4d30cb0eb" xlink:to="loc_us-gaap_CreditFacilityDomain_6e08aecd-09de-444c-8f06-d3d4d30cb0eb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_af810d33-dce1-49fc-a3cd-8650bc4e0315" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_6e08aecd-09de-444c-8f06-d3d4d30cb0eb" xlink:to="loc_us-gaap_CreditFacilityDomain_af810d33-dce1-49fc-a3cd-8650bc4e0315" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_TermFacilityMember_5acb8281-d0be-4e4b-b88f-7e7603f62755" xlink:href="fwrg-20250629.xsd#fwrg_TermFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_af810d33-dce1-49fc-a3cd-8650bc4e0315" xlink:to="loc_fwrg_TermFacilityMember_5acb8281-d0be-4e4b-b88f-7e7603f62755" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_NewDelayedDrawTermFacilityMember_9eb15895-2d23-433a-a159-08117e670817" xlink:href="fwrg-20250629.xsd#fwrg_NewDelayedDrawTermFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_af810d33-dce1-49fc-a3cd-8650bc4e0315" xlink:to="loc_fwrg_NewDelayedDrawTermFacilityMember_9eb15895-2d23-433a-a159-08117e670817" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_NewRevolvingCreditFacilityMember_a80fc21a-51a9-4472-b9f6-97f382cc3f0f" xlink:href="fwrg-20250629.xsd#fwrg_NewRevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_af810d33-dce1-49fc-a3cd-8650bc4e0315" xlink:to="loc_fwrg_NewRevolvingCreditFacilityMember_a80fc21a-51a9-4472-b9f6-97f382cc3f0f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_f46dba71-0e38-4529-84c7-2b5bf6689aa2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_c0c44d62-7997-4cb8-82e5-87b47d056d48" xlink:to="loc_us-gaap_DebtInstrumentAxis_f46dba71-0e38-4529-84c7-2b5bf6689aa2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_f46dba71-0e38-4529-84c7-2b5bf6689aa2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_f46dba71-0e38-4529-84c7-2b5bf6689aa2" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_f46dba71-0e38-4529-84c7-2b5bf6689aa2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_dd6aea1c-70c2-47f1-ab73-a3bdfd4482ab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_f46dba71-0e38-4529-84c7-2b5bf6689aa2" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_dd6aea1c-70c2-47f1-ab73-a3bdfd4482ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_NewFacilitiesMember_d1aa6271-eef9-4aa0-8718-089662ffce81" xlink:href="fwrg-20250629.xsd#fwrg_NewFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_dd6aea1c-70c2-47f1-ab73-a3bdfd4482ab" xlink:to="loc_fwrg_NewFacilitiesMember_d1aa6271-eef9-4aa0-8718-089662ffce81" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_6367fcfc-f5a7-4c70-9824-60c0e163832c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_c0c44d62-7997-4cb8-82e5-87b47d056d48" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_6367fcfc-f5a7-4c70-9824-60c0e163832c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_6367fcfc-f5a7-4c70-9824-60c0e163832c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_6367fcfc-f5a7-4c70-9824-60c0e163832c" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_6367fcfc-f5a7-4c70-9824-60c0e163832c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_946fd192-6aba-494a-81c6-63bf5dc9969d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_6367fcfc-f5a7-4c70-9824-60c0e163832c" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_946fd192-6aba-494a-81c6-63bf5dc9969d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_bb949aa6-2f41-4b65-821b-c02e0ddb53de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_946fd192-6aba-494a-81c6-63bf5dc9969d" xlink:to="loc_us-gaap_LineOfCreditMember_bb949aa6-2f41-4b65-821b-c02e0ddb53de" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_f41e41b5-5155-4fc0-bcba-ec0c3700c534" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_c0c44d62-7997-4cb8-82e5-87b47d056d48" xlink:to="loc_srt_RangeAxis_f41e41b5-5155-4fc0-bcba-ec0c3700c534" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_f41e41b5-5155-4fc0-bcba-ec0c3700c534_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_f41e41b5-5155-4fc0-bcba-ec0c3700c534" xlink:to="loc_srt_RangeMember_f41e41b5-5155-4fc0-bcba-ec0c3700c534_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_40f83566-069b-4e6d-9852-a5ee7b1ff3a2" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_f41e41b5-5155-4fc0-bcba-ec0c3700c534" xlink:to="loc_srt_RangeMember_40f83566-069b-4e6d-9852-a5ee7b1ff3a2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_af533453-3234-4ce1-aa45-d00660e23e2d" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_40f83566-069b-4e6d-9852-a5ee7b1ff3a2" xlink:to="loc_srt_MinimumMember_af533453-3234-4ce1-aa45-d00660e23e2d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_25764ef5-ec87-4809-a584-00e74c8f52c2" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_40f83566-069b-4e6d-9852-a5ee7b1ff3a2" xlink:to="loc_srt_MaximumMember_25764ef5-ec87-4809-a584-00e74c8f52c2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateAxis_8336a2ca-f5be-4bd0-a547-37366d390dbc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VariableRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_c0c44d62-7997-4cb8-82e5-87b47d056d48" xlink:to="loc_us-gaap_VariableRateAxis_8336a2ca-f5be-4bd0-a547-37366d390dbc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_8336a2ca-f5be-4bd0-a547-37366d390dbc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_8336a2ca-f5be-4bd0-a547-37366d390dbc" xlink:to="loc_us-gaap_VariableRateDomain_8336a2ca-f5be-4bd0-a547-37366d390dbc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_00bd806d-9dc2-4dfc-9724-246e566cc18f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_8336a2ca-f5be-4bd0-a547-37366d390dbc" xlink:to="loc_us-gaap_VariableRateDomain_00bd806d-9dc2-4dfc-9724-246e566cc18f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_AdjustedLeverageRateMember_6d7a2860-0cd4-4c47-88a4-6c94988b9334" xlink:href="fwrg-20250629.xsd#fwrg_AdjustedLeverageRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_00bd806d-9dc2-4dfc-9724-246e566cc18f" xlink:to="loc_fwrg_AdjustedLeverageRateMember_6d7a2860-0cd4-4c47-88a4-6c94988b9334" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredOvernightFinancingRateSofrMember_26594b53-7ef1-4fc3-abf8-6fa3aa4cd1d8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SecuredOvernightFinancingRateSofrMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_00bd806d-9dc2-4dfc-9724-246e566cc18f" xlink:to="loc_us-gaap_SecuredOvernightFinancingRateSofrMember_26594b53-7ef1-4fc3-abf8-6fa3aa4cd1d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_a050cc69-1ddc-4f9c-90d3-a01e175c60fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5fe06321-38fc-4202-bb73-a498e056c0f0" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_a050cc69-1ddc-4f9c-90d3-a01e175c60fa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_34b2590c-8ab2-432c-818f-d8d39da6a8d6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromLongTermLinesOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5fe06321-38fc-4202-bb73-a498e056c0f0" xlink:to="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_34b2590c-8ab2-432c-818f-d8d39da6a8d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_9d426dcc-cf4f-4ed2-81a3-ae2dccc5e200" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5fe06321-38fc-4202-bb73-a498e056c0f0" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_9d426dcc-cf4f-4ed2-81a3-ae2dccc5e200" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/DebtScheduleofEstimatedFairValueoftheOutstandingDebtExcludingFinanceLeaseLiabilitiesandFinancingObligationsDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#DebtScheduleofEstimatedFairValueoftheOutstandingDebtExcludingFinanceLeaseLiabilitiesandFinancingObligationsDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/DebtScheduleofEstimatedFairValueoftheOutstandingDebtExcludingFinanceLeaseLiabilitiesandFinancingObligationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_e9ee3da6-39b0-4dd6-9305-0355b6029ed4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_eaad7f7a-0e5a-4f45-937b-9fa5c143c24b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e9ee3da6-39b0-4dd6-9305-0355b6029ed4" xlink:to="loc_us-gaap_DebtInstrumentTable_eaad7f7a-0e5a-4f45-937b-9fa5c143c24b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_cc439e84-e24b-4b37-bb92-cf2e95209168" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_eaad7f7a-0e5a-4f45-937b-9fa5c143c24b" xlink:to="loc_us-gaap_CreditFacilityAxis_cc439e84-e24b-4b37-bb92-cf2e95209168" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_cc439e84-e24b-4b37-bb92-cf2e95209168_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_cc439e84-e24b-4b37-bb92-cf2e95209168" xlink:to="loc_us-gaap_CreditFacilityDomain_cc439e84-e24b-4b37-bb92-cf2e95209168_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_a2c8093b-c38e-49f6-adea-58d2b2d5f72e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_cc439e84-e24b-4b37-bb92-cf2e95209168" xlink:to="loc_us-gaap_CreditFacilityDomain_a2c8093b-c38e-49f6-adea-58d2b2d5f72e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_TermFacilityMember_84b327c3-c3e0-4839-8f45-5d1028347969" xlink:href="fwrg-20250629.xsd#fwrg_TermFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_a2c8093b-c38e-49f6-adea-58d2b2d5f72e" xlink:to="loc_fwrg_TermFacilityMember_84b327c3-c3e0-4839-8f45-5d1028347969" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_c650bdce-1b42-41f1-a644-3fb4c6a88036" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_a2c8093b-c38e-49f6-adea-58d2b2d5f72e" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_c650bdce-1b42-41f1-a644-3fb4c6a88036" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_f308ae36-75fd-4d8f-8e7f-d63ca69edd8e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_eaad7f7a-0e5a-4f45-937b-9fa5c143c24b" xlink:to="loc_us-gaap_DebtInstrumentAxis_f308ae36-75fd-4d8f-8e7f-d63ca69edd8e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_f308ae36-75fd-4d8f-8e7f-d63ca69edd8e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_f308ae36-75fd-4d8f-8e7f-d63ca69edd8e" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_f308ae36-75fd-4d8f-8e7f-d63ca69edd8e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_3d2b456c-42d1-41a4-bd43-f542cf4f4ec2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_f308ae36-75fd-4d8f-8e7f-d63ca69edd8e" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_3d2b456c-42d1-41a4-bd43-f542cf4f4ec2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_NewFacilitiesMember_5c2a8ce0-7840-40de-b918-774cb7f47458" xlink:href="fwrg-20250629.xsd#fwrg_NewFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_3d2b456c-42d1-41a4-bd43-f542cf4f4ec2" xlink:to="loc_fwrg_NewFacilitiesMember_5c2a8ce0-7840-40de-b918-774cb7f47458" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_8626922a-4d89-496d-aee6-a4da3b3841cc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_eaad7f7a-0e5a-4f45-937b-9fa5c143c24b" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_8626922a-4d89-496d-aee6-a4da3b3841cc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_8626922a-4d89-496d-aee6-a4da3b3841cc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_8626922a-4d89-496d-aee6-a4da3b3841cc" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_8626922a-4d89-496d-aee6-a4da3b3841cc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_1030168f-2b94-4392-9db7-27611ad54516" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_8626922a-4d89-496d-aee6-a4da3b3841cc" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_1030168f-2b94-4392-9db7-27611ad54516" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_9ffd0b1f-74d5-436d-8866-b66dda3a39e2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_1030168f-2b94-4392-9db7-27611ad54516" xlink:to="loc_us-gaap_LineOfCreditMember_9ffd0b1f-74d5-436d-8866-b66dda3a39e2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_ec0e5434-9aae-4fe3-98ef-b43586b5cf01" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_eaad7f7a-0e5a-4f45-937b-9fa5c143c24b" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_ec0e5434-9aae-4fe3-98ef-b43586b5cf01" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_ec0e5434-9aae-4fe3-98ef-b43586b5cf01_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_ec0e5434-9aae-4fe3-98ef-b43586b5cf01" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_ec0e5434-9aae-4fe3-98ef-b43586b5cf01_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_b928bee6-c8f8-4900-b457-cee6269d7eb0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_ec0e5434-9aae-4fe3-98ef-b43586b5cf01" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_b928bee6-c8f8-4900-b457-cee6269d7eb0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_5dcdfa33-6c62-451b-b107-2b3783325c60" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_b928bee6-c8f8-4900-b457-cee6269d7eb0" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_5dcdfa33-6c62-451b-b107-2b3783325c60" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_716b155e-7ecc-4ba6-bf08-218f8480b3a0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e9ee3da6-39b0-4dd6-9305-0355b6029ed4" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_716b155e-7ecc-4ba6-bf08-218f8480b3a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_7bc3566d-9122-434a-8aa3-cfec7c8d871d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e9ee3da6-39b0-4dd6-9305-0355b6029ed4" xlink:to="loc_us-gaap_LongTermDebtFairValue_7bc3566d-9122-434a-8aa3-cfec7c8d871d" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/InterestRateSwapsDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#InterestRateSwapsDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/InterestRateSwapsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_0d0ab8f4-0baa-43b4-9235-c5f0d8666296" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_5bd2ac46-4bc8-41d4-9df5-691413cb444a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_0d0ab8f4-0baa-43b4-9235-c5f0d8666296" xlink:to="loc_us-gaap_DerivativeTable_5bd2ac46-4bc8-41d4-9df5-691413cb444a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_9ba61b88-e920-4c1a-8516-09779a57726c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_5bd2ac46-4bc8-41d4-9df5-691413cb444a" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_9ba61b88-e920-4c1a-8516-09779a57726c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_9ba61b88-e920-4c1a-8516-09779a57726c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_9ba61b88-e920-4c1a-8516-09779a57726c" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_9ba61b88-e920-4c1a-8516-09779a57726c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_b2fb0f12-5ea7-4983-8071-f6b792759c6c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_9ba61b88-e920-4c1a-8516-09779a57726c" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_b2fb0f12-5ea7-4983-8071-f6b792759c6c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_b0c36e43-0931-42ec-ab56-ec679caee452" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_b2fb0f12-5ea7-4983-8071-f6b792759c6c" xlink:to="loc_us-gaap_InterestRateSwapMember_b0c36e43-0931-42ec-ab56-ec679caee452" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfInterestRateDerivativesHeld_b058ea79-9603-4288-a174-dc4138b58808" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfInterestRateDerivativesHeld"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_0d0ab8f4-0baa-43b4-9235-c5f0d8666296" xlink:to="loc_us-gaap_NumberOfInterestRateDerivativesHeld_b058ea79-9603-4288-a174-dc4138b58808" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_bc0e20e3-0775-492a-b76c-05fab252117e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_0d0ab8f4-0baa-43b4-9235-c5f0d8666296" xlink:to="loc_us-gaap_DerivativeNotionalAmount_bc0e20e3-0775-492a-b76c-05fab252117e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAverageFixedInterestRate_62d3ac3a-e7b8-429d-a47a-4657924fa16b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeAverageFixedInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_0d0ab8f4-0baa-43b4-9235-c5f0d8666296" xlink:to="loc_us-gaap_DerivativeAverageFixedInterestRate_62d3ac3a-e7b8-429d-a47a-4657924fa16b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_NumberOfAdditionalInterestRateDerivativesEnteredInto_904094c4-2fe4-4cde-89fb-531a4f7142f2" xlink:href="fwrg-20250629.xsd#fwrg_NumberOfAdditionalInterestRateDerivativesEnteredInto"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_0d0ab8f4-0baa-43b4-9235-c5f0d8666296" xlink:to="loc_fwrg_NumberOfAdditionalInterestRateDerivativesEnteredInto_904094c4-2fe4-4cde-89fb-531a4f7142f2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax_3064a87b-c570-41bf-b3c7-01cdb160250f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_0d0ab8f4-0baa-43b4-9235-c5f0d8666296" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax_3064a87b-c570-41bf-b3c7-01cdb160250f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths_c603bcae-fee6-4e00-bcfd-03f9b1a064ec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_0d0ab8f4-0baa-43b4-9235-c5f0d8666296" xlink:to="loc_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths_c603bcae-fee6-4e00-bcfd-03f9b1a064ec" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/EquityandStockBasedCompensationNarrativeDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#EquityandStockBasedCompensationNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/EquityandStockBasedCompensationNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7e034ec8-22de-4cda-9563-24f02b2ba7de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_c5e9fafd-3958-40fc-980a-90d9ada6be7e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7e034ec8-22de-4cda-9563-24f02b2ba7de" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_c5e9fafd-3958-40fc-980a-90d9ada6be7e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_d6bfe156-a3ff-4654-81c7-50e8d46d8661" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_c5e9fafd-3958-40fc-980a-90d9ada6be7e" xlink:to="loc_us-gaap_AwardTypeAxis_d6bfe156-a3ff-4654-81c7-50e8d46d8661" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_d6bfe156-a3ff-4654-81c7-50e8d46d8661_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_d6bfe156-a3ff-4654-81c7-50e8d46d8661" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_d6bfe156-a3ff-4654-81c7-50e8d46d8661_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_2c56eafa-2abc-4410-a9e1-501bf5142987" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_d6bfe156-a3ff-4654-81c7-50e8d46d8661" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_2c56eafa-2abc-4410-a9e1-501bf5142987" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_74a68684-3875-4e6b-9490-254b585a8edb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_2c56eafa-2abc-4410-a9e1-501bf5142987" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_74a68684-3875-4e6b-9490-254b585a8edb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingAxis_ee57ae8a-bbaa-431e-94cf-1e5fef660d3c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_c5e9fafd-3958-40fc-980a-90d9ada6be7e" xlink:to="loc_us-gaap_VestingAxis_ee57ae8a-bbaa-431e-94cf-1e5fef660d3c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingDomain_ee57ae8a-bbaa-431e-94cf-1e5fef660d3c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VestingAxis_ee57ae8a-bbaa-431e-94cf-1e5fef660d3c" xlink:to="loc_us-gaap_VestingDomain_ee57ae8a-bbaa-431e-94cf-1e5fef660d3c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingDomain_b2a4140b-80db-4781-a1e8-7b9d4b17a3e6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VestingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VestingAxis_ee57ae8a-bbaa-431e-94cf-1e5fef660d3c" xlink:to="loc_us-gaap_VestingDomain_b2a4140b-80db-4781-a1e8-7b9d4b17a3e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_888a9971-ce50-49ef-b607-305a6c0f5eb6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheThreeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_b2a4140b-80db-4781-a1e8-7b9d4b17a3e6" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_888a9971-ce50-49ef-b607-305a6c0f5eb6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheOneMember_c7651521-b2a8-483e-82e9-109cfa907a37" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationAwardTrancheOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_b2a4140b-80db-4781-a1e8-7b9d4b17a3e6" xlink:to="loc_us-gaap_ShareBasedCompensationAwardTrancheOneMember_c7651521-b2a8-483e-82e9-109cfa907a37" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_ShareBasedPaymentArrangementTrancheFourMember_b2948955-a8fe-469e-b22e-d416b5418f49" xlink:href="fwrg-20250629.xsd#fwrg_ShareBasedPaymentArrangementTrancheFourMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_b2a4140b-80db-4781-a1e8-7b9d4b17a3e6" xlink:to="loc_fwrg_ShareBasedPaymentArrangementTrancheFourMember_b2948955-a8fe-469e-b22e-d416b5418f49" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_97da59ae-6277-4ce8-a7c9-802298ad2f6c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7e034ec8-22de-4cda-9563-24f02b2ba7de" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_97da59ae-6277-4ce8-a7c9-802298ad2f6c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_6f5d6196-2fa6-4a65-9f3e-e46430e3cd5a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7e034ec8-22de-4cda-9563-24f02b2ba7de" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_6f5d6196-2fa6-4a65-9f3e-e46430e3cd5a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharePrice_905e4a52-13d9-4785-9010-8b11e55ae4cb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7e034ec8-22de-4cda-9563-24f02b2ba7de" xlink:to="loc_us-gaap_SharePrice_905e4a52-13d9-4785-9010-8b11e55ae4cb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_4b809c41-db6c-4d54-8b41-0313a041717a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7e034ec8-22de-4cda-9563-24f02b2ba7de" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_4b809c41-db6c-4d54-8b41-0313a041717a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_6dc79d7a-57fa-4c73-9bdc-1901b5fb59c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7e034ec8-22de-4cda-9563-24f02b2ba7de" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_6dc79d7a-57fa-4c73-9bdc-1901b5fb59c9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense_34834987-4eb2-4023-aaa5-7dab6a5b2fbe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7e034ec8-22de-4cda-9563-24f02b2ba7de" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense_34834987-4eb2-4023-aaa5-7dab6a5b2fbe" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/EquityandStockBasedCompensationScheduleofNonvestedRestrictedStockUnitsActivityDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#EquityandStockBasedCompensationScheduleofNonvestedRestrictedStockUnitsActivityDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/EquityandStockBasedCompensationScheduleofNonvestedRestrictedStockUnitsActivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_058a3ded-be8e-4342-9dc1-8bb9f1434f05" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_e0ea4736-2f25-48a4-8689-23a4df244de1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_058a3ded-be8e-4342-9dc1-8bb9f1434f05" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_e0ea4736-2f25-48a4-8689-23a4df244de1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_c8b10f77-6609-49a8-a9de-982c157cf29d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_e0ea4736-2f25-48a4-8689-23a4df244de1" xlink:to="loc_us-gaap_AwardTypeAxis_c8b10f77-6609-49a8-a9de-982c157cf29d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_c8b10f77-6609-49a8-a9de-982c157cf29d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_c8b10f77-6609-49a8-a9de-982c157cf29d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_c8b10f77-6609-49a8-a9de-982c157cf29d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_dd8301c4-a483-489a-a640-b16d44443b77" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_c8b10f77-6609-49a8-a9de-982c157cf29d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_dd8301c4-a483-489a-a640-b16d44443b77" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_8359482e-d53b-4d34-83f2-b9c7f58cc478" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_dd8301c4-a483-489a-a640-b16d44443b77" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_8359482e-d53b-4d34-83f2-b9c7f58cc478" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_3106a7f0-6d6c-4e3a-8b54-672877c20e13" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_058a3ded-be8e-4342-9dc1-8bb9f1434f05" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_3106a7f0-6d6c-4e3a-8b54-672877c20e13" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_5629c5a0-36b8-434e-abe7-9e8550d670a7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_3106a7f0-6d6c-4e3a-8b54-672877c20e13" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_5629c5a0-36b8-434e-abe7-9e8550d670a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_08f7b830-1475-414a-9985-ccd54875cfb7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_3106a7f0-6d6c-4e3a-8b54-672877c20e13" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_08f7b830-1475-414a-9985-ccd54875cfb7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_cc6ea94c-9617-493f-990d-add293bbcd1f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_3106a7f0-6d6c-4e3a-8b54-672877c20e13" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_cc6ea94c-9617-493f-990d-add293bbcd1f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_c9c1f057-1d7c-4225-bb8b-f799a2a4b83b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_3106a7f0-6d6c-4e3a-8b54-672877c20e13" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_c9c1f057-1d7c-4225-bb8b-f799a2a4b83b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_7a135e37-ab2d-42a6-9574-aa018442f65b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_3b4f5f5a-ad0b-462c-88a0-64075c511a43" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_058a3ded-be8e-4342-9dc1-8bb9f1434f05" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_3b4f5f5a-ad0b-462c-88a0-64075c511a43" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_d0869863-1a38-411f-8790-02ee0e535d48" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_3b4f5f5a-ad0b-462c-88a0-64075c511a43" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_d0869863-1a38-411f-8790-02ee0e535d48" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_839927f4-89d8-4950-b71e-97afcf97300f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_3b4f5f5a-ad0b-462c-88a0-64075c511a43" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_839927f4-89d8-4950-b71e-97afcf97300f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_927b2d36-9c89-4c44-b3f2-5b6f2e75abcb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_3b4f5f5a-ad0b-462c-88a0-64075c511a43" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_927b2d36-9c89-4c44-b3f2-5b6f2e75abcb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_30060fe9-4472-4398-b6f4-f617bfa3b51b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_3b4f5f5a-ad0b-462c-88a0-64075c511a43" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_30060fe9-4472-4398-b6f4-f617bfa3b51b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_cd3aa4e1-e1df-4e50-bdbd-0c15b0761d6d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract_5a62edee-69a4-47b6-ba9d-99882876907d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_058a3ded-be8e-4342-9dc1-8bb9f1434f05" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract_5a62edee-69a4-47b6-ba9d-99882876907d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested_c0d7e26e-43e7-48a8-bd52-f58c18d6336a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract_5a62edee-69a4-47b6-ba9d-99882876907d" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested_c0d7e26e-43e7-48a8-bd52-f58c18d6336a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested_cde24553-ed57-401a-8225-e75c100e39e2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/EquityandStockBasedCompensationScheduleofUnrecognizedStockbasedCompensationExpenseDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#EquityandStockBasedCompensationScheduleofUnrecognizedStockbasedCompensationExpenseDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/EquityandStockBasedCompensationScheduleofUnrecognizedStockbasedCompensationExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfcd9bbf-037c-4490-8f92-1d1440ccfdbe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_541343d5-52a4-4dcb-b21c-958c37e06d58" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfcd9bbf-037c-4490-8f92-1d1440ccfdbe" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_541343d5-52a4-4dcb-b21c-958c37e06d58" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_46fd963a-26dd-498e-9803-239e8f1d2abf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_541343d5-52a4-4dcb-b21c-958c37e06d58" xlink:to="loc_us-gaap_AwardTypeAxis_46fd963a-26dd-498e-9803-239e8f1d2abf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_46fd963a-26dd-498e-9803-239e8f1d2abf_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_46fd963a-26dd-498e-9803-239e8f1d2abf" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_46fd963a-26dd-498e-9803-239e8f1d2abf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0fd9b62c-cb20-484c-836a-7fb3a705f12e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_46fd963a-26dd-498e-9803-239e8f1d2abf" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0fd9b62c-cb20-484c-836a-7fb3a705f12e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_23029893-f1ba-4ac6-ad79-f39e71504c42" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0fd9b62c-cb20-484c-836a-7fb3a705f12e" xlink:to="loc_us-gaap_EmployeeStockOptionMember_23029893-f1ba-4ac6-ad79-f39e71504c42" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_187424bc-c487-46e1-b0d7-f00289ecaec3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0fd9b62c-cb20-484c-836a-7fb3a705f12e" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_187424bc-c487-46e1-b0d7-f00289ecaec3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_2fbf029f-540d-4f27-a9a0-2216f8753ed3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfcd9bbf-037c-4490-8f92-1d1440ccfdbe" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_2fbf029f-540d-4f27-a9a0-2216f8753ed3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_13aea0e8-bca5-433b-9b4e-d39d3532a25c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_cfcd9bbf-037c-4490-8f92-1d1440ccfdbe" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_13aea0e8-bca5-433b-9b4e-d39d3532a25c" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/SegmentInformationScheduleofSegmentReportingInformationbySegmentDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#SegmentInformationScheduleofSegmentReportingInformationbySegmentDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/SegmentInformationScheduleofSegmentReportingInformationbySegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_7e0a3ade-2bb5-47f1-a8ca-7dd4e530bab6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_7e0a3ade-2bb5-47f1-a8ca-7dd4e530bab6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_ed93c4b7-d3af-48c4-8056-72dff2764594" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_7e0a3ade-2bb5-47f1-a8ca-7dd4e530bab6" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_ed93c4b7-d3af-48c4-8056-72dff2764594" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_ed93c4b7-d3af-48c4-8056-72dff2764594_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_ed93c4b7-d3af-48c4-8056-72dff2764594" xlink:to="loc_us-gaap_SegmentDomain_ed93c4b7-d3af-48c4-8056-72dff2764594_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_355528f1-e6c2-44d9-844f-b3fe10c9d95b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_ed93c4b7-d3af-48c4-8056-72dff2764594" xlink:to="loc_us-gaap_SegmentDomain_355528f1-e6c2-44d9-844f-b3fe10c9d95b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_ReportableSegmentMember_07083071-bfe1-4474-893f-80dab250e74a" xlink:href="fwrg-20250629.xsd#fwrg_ReportableSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_355528f1-e6c2-44d9-844f-b3fe10c9d95b" xlink:to="loc_fwrg_ReportableSegmentMember_07083071-bfe1-4474-893f-80dab250e74a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesAbstract_07a7a039-65e0-4191-8e97-7db03379954b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenuesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_RevenuesAbstract_07a7a039-65e0-4191-8e97-7db03379954b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_d4619575-948a-4f13-82e7-eb65f19e4dcc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_07a7a039-65e0-4191-8e97-7db03379954b" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_d4619575-948a-4f13-82e7-eb65f19e4dcc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_6918ff54-fdf0-41f2-a719-7f0ab6ca8e72" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_6918ff54-fdf0-41f2-a719-7f0ab6ca8e72" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostDirectMaterial_a86a1837-cc6a-4f31-a283-5dddfeccd800" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostDirectMaterial"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_6918ff54-fdf0-41f2-a719-7f0ab6ca8e72" xlink:to="loc_us-gaap_CostDirectMaterial_a86a1837-cc6a-4f31-a283-5dddfeccd800" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostDirectLabor_5105a5ab-9c70-4783-8c16-59bec56326ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostDirectLabor"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_6918ff54-fdf0-41f2-a719-7f0ab6ca8e72" xlink:to="loc_us-gaap_CostDirectLabor_5105a5ab-9c70-4783-8c16-59bec56326ee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCostOfOperatingRevenue_ab70c5dd-1ba0-47f3-b4d2-99afbda6f622" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherCostOfOperatingRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_6918ff54-fdf0-41f2-a719-7f0ab6ca8e72" xlink:to="loc_us-gaap_OtherCostOfOperatingRevenue_ab70c5dd-1ba0-47f3-b4d2-99afbda6f622" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSoldOverhead_f45de064-4e5f-42b4-9f3d-6b4db8dcfb94" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServicesSoldOverhead"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_6918ff54-fdf0-41f2-a719-7f0ab6ca8e72" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSoldOverhead_f45de064-4e5f-42b4-9f3d-6b4db8dcfb94" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreOpeningCosts_e5190ddd-89de-48ee-a0e7-2a882eb21c91" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreOpeningCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortizationAbstract_6918ff54-fdf0-41f2-a719-7f0ab6ca8e72" xlink:to="loc_us-gaap_PreOpeningCosts_e5190ddd-89de-48ee-a0e7-2a882eb21c91" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_a121305b-c6a1-4756-a6de-c367f269fb93" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_a121305b-c6a1-4756-a6de-c367f269fb93" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_7134b93a-c55f-4bfb-90cb-e058e53d982a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_7134b93a-c55f-4bfb-90cb-e058e53d982a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_f54b4e0f-663f-4de6-9a32-60153d5c7d44" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_DepreciationAndAmortization_f54b4e0f-663f-4de6-9a32-60153d5c7d44" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingOtherItemAmount_25829d77-5521-4914-8d17-8a25d0bb8f9a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingOtherItemAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_SegmentReportingOtherItemAmount_25829d77-5521-4914-8d17-8a25d0bb8f9a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_d37c1fa5-76c9-493d-a4f2-c2938df20384" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_InterestExpenseNonoperating_d37c1fa5-76c9-493d-a4f2-c2938df20384" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_325c2484-7858-48cc-9fa1-ce9fd519da62" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_NonoperatingIncomeExpense_325c2484-7858-48cc-9fa1-ce9fd519da62" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_aa6a2849-0747-4afb-a62c-1d58686a05e5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_aa6a2849-0747-4afb-a62c-1d58686a05e5" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_36af8210-e886-4d87-987b-ac9443c68c39" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_42cedf17-f7eb-477f-8326-0b1a79e03f6b" xlink:to="loc_us-gaap_NetIncomeLoss_36af8210-e886-4d87-987b-ac9443c68c39" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.firstwatch.com/role/NetIncomePerCommonShareDetails" xlink:type="simple" xlink:href="fwrg-20250629.xsd#NetIncomePerCommonShareDetails"/>
  <link:definitionLink xlink:role="http://www.firstwatch.com/role/NetIncomePerCommonShareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_0cfa4656-acbf-477c-937c-b78a0a665dbc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_eff7c3ab-0dce-46d4-aed7-cac3e7ea5f80" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_0cfa4656-acbf-477c-937c-b78a0a665dbc" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_eff7c3ab-0dce-46d4-aed7-cac3e7ea5f80" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_bcf046e8-6a2f-4f23-a773-ac5b1c5d8be8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_eff7c3ab-0dce-46d4-aed7-cac3e7ea5f80" xlink:to="loc_us-gaap_AwardTypeAxis_bcf046e8-6a2f-4f23-a773-ac5b1c5d8be8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bcf046e8-6a2f-4f23-a773-ac5b1c5d8be8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_bcf046e8-6a2f-4f23-a773-ac5b1c5d8be8" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bcf046e8-6a2f-4f23-a773-ac5b1c5d8be8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_c55c7172-80e4-48db-86c9-b94406e66039" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_bcf046e8-6a2f-4f23-a773-ac5b1c5d8be8" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_c55c7172-80e4-48db-86c9-b94406e66039" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_3c3d6db3-1cea-4d73-bdcb-d3b8406f4653" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_c55c7172-80e4-48db-86c9-b94406e66039" xlink:to="loc_us-gaap_EmployeeStockOptionMember_3c3d6db3-1cea-4d73-bdcb-d3b8406f4653" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_1687176c-c690-4195-aa7f-57c8af00217c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_c55c7172-80e4-48db-86c9-b94406e66039" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_1687176c-c690-4195-aa7f-57c8af00217c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_e693075c-b131-4996-a5fc-cb94eff506ce" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_0cfa4656-acbf-477c-937c-b78a0a665dbc" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_e693075c-b131-4996-a5fc-cb94eff506ce" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_39cbab86-e49a-4b51-87c5-5ecaa2c359a3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_e693075c-b131-4996-a5fc-cb94eff506ce" xlink:to="loc_us-gaap_NetIncomeLoss_39cbab86-e49a-4b51-87c5-5ecaa2c359a3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract_fac800d2-42ed-450c-91d2-dfd2af62015a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_0cfa4656-acbf-477c-937c-b78a0a665dbc" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract_fac800d2-42ed-450c-91d2-dfd2af62015a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_df30d37f-9d98-4998-809f-6a922e83b381" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract_fac800d2-42ed-450c-91d2-dfd2af62015a" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_df30d37f-9d98-4998-809f-6a922e83b381" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_5f7c393f-197f-4ed6-86c6-1ab4b6cbfd6c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasicAbstract_fac800d2-42ed-450c-91d2-dfd2af62015a" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_5f7c393f-197f-4ed6-86c6-1ab4b6cbfd6c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_530552aa-0bb0-42b4-b495-c2aaba6fe56e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_0cfa4656-acbf-477c-937c-b78a0a665dbc" xlink:to="loc_us-gaap_EarningsPerShareBasic_530552aa-0bb0-42b4-b495-c2aaba6fe56e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_80f26e00-9d94-4574-b7a1-1d6ca547f41e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_0cfa4656-acbf-477c-937c-b78a0a665dbc" xlink:to="loc_us-gaap_EarningsPerShareDiluted_80f26e00-9d94-4574-b7a1-1d6ca547f41e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_43b0ba67-bdbf-40ed-a4b6-9efb0885b822" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_0cfa4656-acbf-477c-937c-b78a0a665dbc" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_43b0ba67-bdbf-40ed-a4b6-9efb0885b822" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.xsd#eedm"/>
  <link:definitionLink xlink:role="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrentAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_PortionOfLongTermDebtCurrent_34bbbeac-c92c-4416-b60a-365b731c951d" xlink:href="fwrg-20250629.xsd#fwrg_PortionOfLongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:to="loc_fwrg_PortionOfLongTermDebtCurrent_34bbbeac-c92c-4416-b60a-365b731c951d" xlink:type="arc" order="41"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#IndividualsOnly"/>
  <link:definitionLink xlink:role="http://xbrl.sec.gov/ecd/role/IndividualsOnly" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ecd_AllIndividualsMember" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_AllIndividualsMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_fwrg_LauraSorensenMember_ae955e6f-caeb-4181-9612-c65a47453c9c" xlink:href="fwrg-20250629.xsd#fwrg_LauraSorensenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ecd_AllIndividualsMember" xlink:to="loc_fwrg_LauraSorensenMember_ae955e6f-caeb-4181-9612-c65a47453c9c" xlink:type="arc" order="2"/>
  </link:definitionLink>
</link:linkbase>
