'dukedom' originates from a combination of elements: 'duke' (from Old French 'duc', ultimately from Latin 'dux'), where 'dux' meant 'leader', and the suffix '-dom' (from Old English 'dōm'), where 'dōm' meant 'state, jurisdiction'.

'dukedom' changed from Middle English forms such as 'dukedome' (and related spellings like 'ducdom') and eventually became the modern English word 'dukedom'.

Initially it referred to the office or jurisdiction associated with a duke; over time it has come to be used chiefly for the territory or domain ruled by a duke.