'archfounder' originates from Modern English, specifically by combining the prefix 'arch-' (from Greek 'arkhē' / 'arkhos' meaning 'chief, principal, or ruler') and the noun 'founder' (ultimately from Latin 'fundare' meaning 'to lay a foundation', via Old French/Anglo-Norman).

'arch-' entered English as a productive prefix via Old French and Medieval Latin from Greek roots such as 'arkhē'/'arkhos', while 'founder' derives from Old French (e.g. 'fondre'/'fondier') and Latin 'fundare'. The compound 'archfounder' is formed in Modern English by directly combining these elements to mean a chief founder.

Initially the parts meant 'chief' and 'one who lays a foundation'; over time the compounded form came to mean 'the principal or most important founder' in current usage.