'antiopiumist' originates from English coinage combining the prefix 'anti-' (from Greek 'anti-' meaning 'against'), the noun 'opium' (from Latin 'opium', from Greek 'opion' meaning 'poppy juice'), and the agentive suffix '-ist' (from Greek/Latin via French, meaning 'person who').

'antiopiumist' was formed in the 19th century by compounding 'anti-' + 'opium' + '-ist' and appeared in discourse surrounding the Opium Wars and late 19th-century campaigns against the opium trade; it remained a descriptive English term for opponents of opium.

Initially it meant 'a person opposed to opium or the opium trade', and this core meaning has remained largely unchanged over time.