'antivenom' originates from the prefix 'anti-' (from Greek 'anti' meaning 'against') combined with 'venom' (from Latin 'venenum' meaning 'poison').

'venom' comes from Latin 'venenum' and passed into Old French as 'venin' and Middle English as 'venym/venom'; the modern compound 'antivenom' was formed in modern English (19th–20th century) by adding the prefix 'anti-' to 'venom'.

Initially, words related to 'venenum' referred broadly to 'poison'; the compound 'antivenom' came to mean specifically a medical serum that neutralizes animal venoms.