man-of-war
(military, archaic except humorous) A man whose occupation is fighting in wars; a soldier, a warrior.
(military, nautical, chiefly historical) A powerful armed naval vessel, primarily one armed with cannon and propelled by sails; a warship.
[N]o wonder that, although junior partner, and as modest as he was high-spirited, he trod his counting-house floor with a step vigorous and springy as the young captain of a man-of-war, for he felt that he was an emancipated slave; nay, more, a British merchant.
His little man-o'-war top and unmentionables were full of sand but Cissy was a past mistress in the art of smoothing over life's tiny troubles and and[sic] very quickly not one speck of sand was to be seen on his smart little suit.
I have a boatswain who pipes, Livesey; so things shall go man-o-war fashion on board the good ship Hispaniola.
(obsolete, rare) A sailor serving on board an armed naval vessel.
Man-of-war bird or (obsolete) man-of-war hawk (any of a number of seabirds, especially one which attacks other seabirds to take their food).
(archaic) A frigatebird (family Fregatidae), especially the magnificent frigatebird (Fregata magnificens).
(US) The Arctic skua (Stercorarius parasiticus).
Physalia physalis, a jellyfish-like marine cnidarian consisting of a floating colony of hydrozoans attached to a float.