'antisepticise' originates from Greek via Late Latin and French, specifically the word 'antiseptikos' and Late Latin 'antisepticus', where 'anti-' meant 'against' and 'septikos' meant 'causing putrefaction', and the verb-forming suffix '-ise' (from Greek '-izein' via Latin/French) meant 'to make or become'.

'antisepticise' changed from the adjective 'antiseptic' (from 'antiseptikos') with the addition of the verb-forming suffix '-ize' to form 'antisepticize' in Modern English; the British spelling variant 'antisepticise' developed as an alternative to the -ize spelling.

Initially, it meant 'to prevent or counteract putrefaction', but over time it evolved into its current meaning of 'to make something antiseptic; to disinfect or sterilise'.