'antidogmatist' originates from modern English, formed from the prefix 'anti-' (from Greek 'anti' meaning 'against') combined with 'dogmatist' (from Greek 'dogma' meaning 'opinion' or 'that which seems to one to be true').

'antidogmatist' was formed by analogy from earlier English formations using 'anti-' + a noun (e.g. 'antagonist'); 'dogmatist' itself derives from 'dogma' (Greek 'dógnma') and the agent suffix '-ist', yielding 'dogmatist', and the compound 'antidogmatist' follows as 'one against dogmatism'.

Initially the components meant 'against' + 'opinion/teaching', and the compound has come to mean specifically 'one who opposes rigid or authoritative doctrinal assertions' in modern usage.