'conjunction-free' originates from English, specifically the words 'conjunction' and 'free', where 'conjunction' ultimately comes from Latin 'conjunctio' (from 'con-' meaning 'together' and 'jungere'/'junct-' meaning 'to join'), and 'free' comes from Old English 'freo' meaning 'not in bondage' or 'without'.

'conjunction' changed from Latin 'conjunctio' into Old French/Latin-influenced forms and Middle English 'conjunctioun' before becoming the modern English 'conjunction'; 'free' comes from Old English 'freo' and evolved into the modern adjective 'free' and later the productive suffix '-free' used in compounds (e.g. 'sugar-free'), which gave rise to compounds like 'conjunction-free' in modern English.

Initially, the components meant 'joining' (for 'conjunction') and 'not in bondage/without' (for 'free'); the compound 'conjunction-free' therefore developed the literal combined sense 'without conjunctions', used to describe language or structures that omit conjunctions.