'archexorcist' originates from Modern English, specifically a compound of the prefix 'arch-' (from Greek 'arkhos') and the noun 'exorcist' (from Greek via Latin), where 'arch-' meant 'chief/principal' and 'exorcist' meant 'one who performs exorcisms'.

'archexorcist' is a modern English coinage formed by combining the long-established prefix 'arch-' (used to indicate highest rank) with 'exorcist' (itself from Greek exorkizein via Latin/Old French); the compound follows the pattern of formations like 'archbishop' and 'archenemy'.

Initially formed to mean simply 'chief exorcist', the term can also imply a ceremonial or formal title for the person who oversees particularly important or high‑level exorcisms.