'anti-Catholicism' originates from the prefix 'anti-' (from Greek anti meaning 'against') combined with 'Catholicism' (from Late Latin 'catholicus' < Greek 'katholikos' meaning 'universal') and the noun-forming suffix '-ism' (from Greek -ismos/Latin -ismus).

'anti-Catholicism' developed in English by combining 'anti-' + 'Catholicism'; 'Catholicism' itself evolved from Greek 'katholikos' → Late Latin/Medieval Latin 'catholicus' → Old/Middle English 'catholic' and then the noun 'Catholicism', with the modern compounded form appearing in modern English usage from the 18th–19th centuries onward.

Initially it meant 'opposition to the doctrines or institutions of the Catholic Church'; over time the term retained that core but broadened to cover social prejudice, discrimination, and political movements targeting Catholics.