'age-acceptance' originates from Modern English, specifically the words 'age' and 'acceptance', where 'age' ultimately comes from Latin 'aetas' meaning 'age' and 'acceptance' comes from Latin 'acceptare' (from 'accipere') meaning 'to receive or accept'.

'age' changed from Latin 'aetas' to Old French 'age' and then to Middle English 'age', becoming the modern English 'age'. 'acceptance' evolved from Latin 'accipere' to Late Latin 'acceptare', to Old French 'acceptance', and into Middle English 'acceptance', eventually becoming modern English 'acceptance'.

Initially, 'age' referred broadly to a period or length of life and 'acceptance' to the act of receiving; over time the compound has come to mean accepting or approving of age or the aging process, and more broadly social recognition of people of different ages.