'antidemocratic' originates from Greek elements: the prefix 'anti-' (from Greek 'anti' meaning 'against') combined with 'democratic', from Greek 'demokratia' where 'demos' meant 'people' and 'kratos' meant 'power' or 'rule'.

'antidemocratic' developed by attaching the productive English suffix '-al' and adverbial '-ly' to form 'antidemocratically'. The root 'democracy' itself came from Greek 'demokratia' → Late Latin/Medieval Latin 'democratia' → Middle French 'démocratie' → Middle English 'democracy', and the prefix 'anti-' was borrowed from Greek into Latin and then into English.

Initially, the components meant 'against' + 'rule by the people'; over time the compound has come to mean broadly 'opposed to democratic principles' and the adverb 'antidemocratically' 'in a way that opposes democracy'.