'papism' originates from English formation of 'papist' + the suffix '-ism', where 'papist' ultimately comes from Latin 'papa' (from Greek 'pappas') meaning 'father' or 'pope', and '-ism' denotes 'belief or system'.

'papism' developed from Middle English and earlier forms: Latin 'papa' -> Old French 'pape' -> Middle English 'pape/papest' leading to the adjective/noun 'papist', and then the noun 'papism' was formed in English to denote the system or doctrine associated with papists.

Initially it referred simply to support of the pope or the papal office; over time it has often been used pejoratively to mean 'Roman Catholicism' or the perceived abuses of papal authority.