bombardier vs aircrewman

bombardier and aircrewman both are nouns.

Word	Noun	Adjective	Verb	Adverb
bombardier	Yes	No	No	No
aircrewman	Yes	No	No	No

As nouns, aircrewman is a hypernym of bombardier; that is, aircrewman is a word with a broader meaning than bombardier:

bombardier: the member of a bomber crew responsible for using the bombsight and releasing the bombs on the target
aircrewman: a member of an aircrew

bombardier (noun)	aircrewman (noun)
the member of a bomber crew responsible for using the bombsight and releasing the bombs on the target	a member of an aircrew
a noncommissioned officer in the British artillery