<?xml version="1.0" encoding="UTF-8"?><!-- Generated by Broadridge Financial Solutions Inc --><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" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:xbrldt="http://xbrl.org/2005/xbrldt"  xmlns:macquarie="http://macquarie/20260331">
			<link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#ProspectusOnly" roleURI="http://xbrl.sec.gov/rr/role/ProspectusOnly"/>
			<link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#SeriesOnly" roleURI="http://xbrl.sec.gov/oef/role/SeriesOnly"/>
			<link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#ClassOnly" roleURI="http://xbrl.sec.gov/oef/role/ClassOnly"/>
			<link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#RiskOnly" roleURI="http://xbrl.sec.gov/rr/role/RiskOnly"/>
			<link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#PerformanceMeasureOnly" roleURI="http://xbrl.sec.gov/rr/role/PerformanceMeasureOnly"/>
			<link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default"/>
			<link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain"/>
			<link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension"/>
			<link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member"/>
			<link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" arcroleURI="http://xbrl.org/int/dim/arcrole/all"/>
		<link:definitionLink xlink:role="http://xbrl.sec.gov/rr/role/ProspectusOnly" xlink:type="extended"><link:loc xlink:type="locator" xlink:label="DocumentDomain" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentDomain"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_Dmarchsmallcapcorepro_2514Member" xlink:label="Dmarchsmallcapcorepro_2514Member" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_Dmarchsmallcapvaluepro_2516Member" xlink:label="Dmarchsmallcapvaluepro_2516Member" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_Dmarchwealthbuilderpro_2512Member" xlink:label="Dmarchwealthbuilderpro_2512Member" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_Dmarchdgefvsai_2506Member" xlink:label="Dmarchdgefvsai_2506Member" /><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DocumentDomain" xlink:to="Dmarchsmallcapcorepro_2514Member" use="optional" order="1.0"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DocumentDomain" xlink:to="Dmarchsmallcapvaluepro_2516Member" use="optional" order="2.0"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DocumentDomain" xlink:to="Dmarchwealthbuilderpro_2512Member" use="optional" order="3.0"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DocumentDomain" xlink:to="Dmarchdgefvsai_2506Member" use="optional" order="4.0"/></link:definitionLink><link:definitionLink xlink:role="http://xbrl.sec.gov/oef/role/SeriesOnly" xlink:type="extended"><link:loc xlink:type="locator" xlink:label="dei_EntityDomain" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityDomain"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_S000002400Member" xlink:label="S000002400Member" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_S000002401Member" xlink:label="S000002401Member" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_S000002399Member" xlink:label="S000002399Member" /><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_EntityDomain" xlink:to="S000002400Member" use="optional" order="2.0"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_EntityDomain" xlink:to="S000002401Member" use="optional" order="3.0"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_EntityDomain" xlink:to="S000002399Member" use="optional" order="4.0"/></link:definitionLink><link:definitionLink xlink:role="http://xbrl.sec.gov/oef/role/ClassOnly" xlink:type="extended"><link:loc xlink:type="locator" xlink:label="ShareClassDomain" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_ShareClassDomain"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006373Member"  xlink:label="C000006373Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006377Member"  xlink:label="C000006377Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006368Member"  xlink:label="C000006368Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006374Member"  xlink:label="C000006374Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006379Member"  xlink:label="C000006379Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006370Member"  xlink:label="C000006370Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006375Member"  xlink:label="C000006375Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006380Member"  xlink:label="C000006380Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006371Member"  xlink:label="C000006371Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006376Member"  xlink:label="C000006376Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006381Member"  xlink:label="C000006381Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000006372Member"  xlink:label="C000006372Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000171461Member"  xlink:label="C000171461Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000171462Member"  xlink:label="C000171462Member"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_C000240402Member"  xlink:label="C000240402Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006373Member" order="2" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006377Member" order="3" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006368Member" order="4" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006374Member" order="5" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006379Member" order="6" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006370Member" order="7" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006375Member" order="8" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006380Member" order="9" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006371Member" order="10" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006376Member" order="11" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006381Member" order="12" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000006372Member" order="13" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000171461Member" order="14" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000171462Member" order="15" /><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain"  use="optional" xlink:to="C000240402Member" order="16" /></link:definitionLink><link:definitionLink xlink:role="http://xbrl.sec.gov/rr/role/PerformanceMeasureOnly" xlink:type="extended"><link:loc xlink:type="locator" xlink:label="PerformanceMeasureDomain" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_PerformanceMeasureDomain"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20260126141Member" xlink:label="bench20260126141Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PerformanceMeasureDomain"  use="optional" xlink:to="bench20260126141Member" order="1516.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20260319196Member" xlink:label="bench20260319196Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PerformanceMeasureDomain"  use="optional" xlink:to="bench20260319196Member" order="1518.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20260319197Member" xlink:label="bench20260319197Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PerformanceMeasureDomain"  use="optional" xlink:to="bench20260319197Member" order="1520.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20260319202Member" xlink:label="bench20260319202Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PerformanceMeasureDomain"  use="optional" xlink:to="bench20260319202Member" order="1522.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20251120112Member" xlink:label="bench20251120112Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PerformanceMeasureDomain"  use="optional" xlink:to="bench20251120112Member" order="1523.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20260319203Member" xlink:label="bench20260319203Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PerformanceMeasureDomain"  use="optional" xlink:to="bench20260319203Member" order="1524.0" /></link:definitionLink><link:definitionLink xlink:role="http://xbrl.sec.gov/rr/role/RiskOnly" xlink:type="extended"><link:loc xlink:type="locator" xlink:label="oef_AllRisksMember" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_AllRisksMember"/><link:loc xlink:type="locator" xlink:label="us-gaap_FixedIncomeSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FixedIncomeSecuritiesMember"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember" xlink:to="us-gaap_FixedIncomeSecuritiesMember" order="11" xbrldt:closed="true"/><link:loc xlink:type="locator" xlink:label="us-gaap_MortgageBackedSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MortgageBackedSecuritiesMember"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember" xlink:to="us-gaap_MortgageBackedSecuritiesMember" order="15" xbrldt:closed="true"/><link:loc xlink:type="locator" xlink:label="us-gaap_CollateralizedMortgageObligationsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollateralizedMortgageObligationsMember"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember" xlink:to="us-gaap_CollateralizedMortgageObligationsMember" order="16" xbrldt:closed="true"/><link:loc xlink:type="locator" xlink:label="us-gaap_CommercialMortgageBackedSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember" xlink:to="us-gaap_CommercialMortgageBackedSecuritiesMember" order="18" xbrldt:closed="true"/><link:loc xlink:type="locator" xlink:label="us-gaap_AssetBackedSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetBackedSecuritiesMember"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember" xlink:to="us-gaap_AssetBackedSecuritiesMember" order="20" xbrldt:closed="true"/><link:loc xlink:type="locator" xlink:label="us-gaap_SovereignDebtSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SovereignDebtSecuritiesMember"/><link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember" xlink:to="us-gaap_SovereignDebtSecuritiesMember" order="25" xbrldt:closed="true"/><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20251120118Member" xlink:label="bench20251120118Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench20251120118Member" order="154.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench2025112092Member" xlink:label="bench2025112092Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench2025112092Member" order="155.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench2025112091Member" xlink:label="bench2025112091Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench2025112091Member" order="156.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20260126137Member" xlink:label="bench20260126137Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench20260126137Member" order="157.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench2025112095Member" xlink:label="bench2025112095Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench2025112095Member" order="158.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench2025112090Member" xlink:label="bench2025112090Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench2025112090Member" order="159.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench2025112099Member" xlink:label="bench2025112099Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench2025112099Member" order="1510.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20260126138Member" xlink:label="bench20260126138Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench20260126138Member" order="1511.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20251120103Member" xlink:label="bench20251120103Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench20251120103Member" order="1512.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20251120100Member" xlink:label="bench20251120100Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench20251120100Member" order="1513.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20251218133Member" xlink:label="bench20251218133Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench20251218133Member" order="1514.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20251120107Member" xlink:label="bench20251120107Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench20251120107Member" order="1515.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20260219149Member" xlink:label="bench20260219149Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench20260219149Member" order="1516.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench2025112093Member" xlink:label="bench2025112093Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench2025112093Member" order="1517.0" /><link:loc xlink:type="locator" xlink:href="macquarie-20260331.xsd#macquarie_bench20260319201Member" xlink:label="bench20260319201Member"/><link:definitionArc  xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="oef_AllRisksMember"  use="optional" xlink:to="bench20260319201Member" order="1518.0" /></link:definitionLink></link:linkbase>
