'Apollinarism' originates from Medieval Latin, specifically the word 'Apollinarismus', where 'Apollinaris' referred to the name 'Apollinaris' (meaning 'of Apollo' or 'belonging to Apollo') and the suffix '-ismus' formed nouns denoting doctrines or systems.

'Apollinarism' changed from the Medieval Latin word 'Apollinarismus' (itself based on the personal name 'Apollinaris', Latinized from Greek) and eventually became the modern English word 'Apollinarism'.

Initially, it meant 'the doctrine associated with Apollinaris' and over time has retained that specialized theological meaning referring to the specific Christological teaching attributed to Apollinaris.