'antiskeptic' originates from Modern English, specifically the prefix 'anti-' and the noun 'skeptic', where 'anti-' meant 'against' and 'skeptic' meant 'one who questions or examines'.

'skeptic' comes from Greek 'skeptikos' (σκέπτικος) via Latin/Medieval Latin and Middle English; 'anti-' is from Greek 'anti-' (ἀντί). These elements combined in Modern English to form the compound 'antiskeptic'.

Initially the parts meant 'against' + 'one who questions'; combined, the coinage has been used to mean 'against skepticism' or 'opposed to skeptical attitudes', a sense consistent with its components.