'antitheological' originates from Modern English, specifically combining the prefix 'anti-' (from Greek 'anti', where 'anti-' meant 'against') and 'theological' (from Greek 'theologia', where 'theo-' meant 'god' and '-logia' meant 'study/speech').

'theologia' (Greek) passed into Late Latin as 'theologia' and then into English as 'theology'/'theological'; the prefix 'anti-' (Greek 'anti') was attached in Modern English to form the compound 'antitheological'.

Initially formed as a literal compound meaning 'against theology' (i.e., against the study or doctrines of God); it has retained that core sense and is used to describe opposition to theological claims or frameworks.