'antidote' originates from Greek, specifically the word 'antidoton', where 'anti-' meant 'against' and 'didonai' meant 'to give'.

'antidoton' passed into Latin as 'antidotum', then into Old French and Middle English, eventually becoming the modern English word 'antidote'.

Initially it meant 'something given against (a poison)', and over time it has kept that sense while also acquiring figurative uses meaning 'a remedy or countermeasure'.