privateer vs crewman

privateer and crewman both are nouns.

Word	Noun	Adjective	Verb	Adverb
privateer	Yes	No	No	No
crewman	Yes	No	No	No

As nouns, crewman is a hypernym of privateer; that is, crewman is a word with a broader meaning than privateer:

Other hypernyms of privateer include crew member, officer, ship's officer.

privateer (noun)	crewman (noun)
a privately owned warship commissioned to prey on the commercial shipping or warships of an enemy nation	a member of a work crew
an officer or crew member of a privateer	a member of a flight crew
	any member of a ship's crew