'antonymy' originates from Greek, specifically the word 'antonymia', where 'anti-' meant 'against' and 'onoma' (or 'onyma') meant 'name'.

'antonymy' changed from the Greek word 'antonymia' through Medieval Latin/French forms and eventually became the modern English word 'antonymy'.

Initially, it meant 'opposite name' (a name given to something opposite); over time it evolved into its current meaning of 'the relationship between words that are opposites'.