'romance-affirming' originates from Modern English, specifically the words 'romance' and 'affirming', where 'romance' ultimately comes from Old French 'romanz' (from Medieval Latin 'romanicus') meaning 'a tale in the vernacular/relating to the Romance languages', and 'affirming' derives from Latin 'affirmare', where 'ad-' (in related forms) meant 'to/toward' and 'firmare' meant 'to make firm or confirm'.

'romance' changed from Old French 'romanz' and Medieval Latin 'romanicus' into the English noun 'romance'; 'affirmare' passed into Old French/Latin-influenced vocabulary and became English 'affirm' and its present participle 'affirming'. These elements were combined in Modern English to form the compound adjective 'romance-affirming'.

Originally, 'romance' referred to a narrative or things relating to the Romance (vernacular) languages and 'affirm' meant 'to make firm or confirm'; over time the compound evolved to mean 'confirming or supporting romantic sentiment' in contemporary usage.