'antiauthoritarianism' is formed in modern English by the prefix 'anti-' (from Greek via Latin meaning 'against') + 'authoritarianism' (the noun form of 'authoritarian') + the suffix '-ism' (from Greek/Latin/French indicating a doctrine or practice).

'authoritarian' derives from 'authority' (from Latin 'auctoritas'), which yielded 'authoritarian' in English; adding the suffix '-ism' produced 'authoritarianism'; the prefix 'anti-' was later attached to form 'antiauthoritarianism' to denote opposition to that doctrine.

Originally used to describe specific political opposition to authoritarian regimes, the term broadened to include a wider stance against hierarchical or coercive authority in social and cultural contexts.