'antiopiumite' originates from modern English formation, specifically combining the prefix 'anti-' (from Greek 'anti' meaning 'against'), the noun 'opium' (from Latin/Greek 'opion' meaning 'poppy juice'), and the suffix '-ite' (from Greek '-ites' via Old French, meaning 'member' or 'follower').

'antiopiumite' changed from the compound phrase 'anti-opium' + the agent-forming suffix '-ite', a construction found in 19th-century English political and reform contexts, and eventually became the coined noun 'antiopiumite' in modern English.

Initially, it meant 'a member of or participant in an anti-opium group', but over time it has been used more broadly to mean 'any person who opposes opium use or trade'.