'antivenom' originates from Modern English, specifically the prefix 'anti-' (from Greek) meaning 'against' and 'venom' from Latin 'venenum' meaning 'poison'.

'venom' entered English via Old French 'venin' from Latin 'venenum'; 'antivenom' was formed in English by combining the element 'anti-' with 'venom' to denote a substance acting against venom.

Initially it meant 'a preparation that counteracts venom', and over time this core meaning has remained largely unchanged as the modern medical term for such sera.