From pope + -ish.

• (British) IPA: /ˈpəʊpɪʃ/
• (America) enPR: pōʹpĭsh, IPA: /ˈpoʊpɪʃ/

popish

1. (derogatory, used by early Protestants) of or pertaining to Roman Catholicism
   • 1629, Joseph Hall, The Reconciler:

     I do, therefore, much blame the petulcity of whatsoever author, that should dare to impute a Popish affection to him […]

2. (derogatory) acting like, or holding beliefs similar to, the pope.

• See Roman Catholic § Synonyms

• pope
• popess

popish