'archduchy' originates from a combination of the prefix 'arch-' (from Greek 'arkhós' meaning 'chief, principal') and 'duchy' (from Old French/Medieval Latin 'duchie'/'ducatus', ultimately from Latin 'dux' meaning 'leader').

'archduchy' entered English as a calque and loan-influenced term in the late medieval to early modern period, influenced by German 'Erzherzogtum' ('Erz-' = 'arch-', 'Herzog' = 'duke') and by Old French/Medieval Latin forms; over time these elements combined into the modern English form 'archduchy'.

Initially used to denote specifically the territorial domain or the rank of an archduke in certain European dynasties; it has retained that historical/political meaning and is now mainly used in historical or formal contexts.