a petty officer on a merchant ship or a warrant officer on a warship who is responsible for the maintenance of the ship and its equipment
WordReference Random House Learner's Dictionary of American English © 2026
boat•swain or bo's'n or bo•sun /ˈboʊsən/USA pronunciation
n. [countable]
WordReference Random House Unabridged Dictionary of American English © 2026- Nautical, Military, Naval Termsa petty officer on a warship or on a merchant vessel who is in charge of rigging, anchors, cables, and other equipment.
boat•swain
(bō′sən; spelling pron. bōt′swān′),USA pronunciation n.
- Nautical, Military, Naval Termsa warrant officer on a warship, or a petty officer on a merchant vessel, in charge of rigging, anchors, cables, etc.
- late Middle English bote-swayn. See boat, swain 1400–50
Collins Concise English Dictionary © HarperCollins Publishers::
'boatswain' also found in these entries (note: many are not synonyms or translations):
able seaman
- bo's'n
- boatswain bird
- boatswain's chair
- boatswain's pipe
- bosun
- breast
- buffer
- petty officer
- pipe
- sherang
- tropic bird