'papist' originates from Middle French 'papiste' and Late Latin 'papista', ultimately from Greek 'pappas' (later Latin 'papa'), where 'pappas'/'papa' meant 'father' and the suffix '-ist' (via Latin/French '-ista'/'-iste') denotes an adherent.

'papist' changed from Middle French 'papiste' and Late Latin 'papista' and entered Early Modern English (16th century) as 'papist', used in religious and political polemics.

Initially it meant 'an adherent or follower of the Pope' (a descriptive sense), but over time—especially in Protestant and polemical contexts—it evolved into a derogatory term for Roman Catholics.