gun room vs military quarters

gun room and military quarters both are nouns.

Word	Noun	Adjective	Verb	Adverb
gun room	Yes	No	No	No
military quarters	Yes	No	No	No

As nouns, military quarters is a hypernym of gun room; that is, military quarters is a word with a broader meaning than gun room:

gun room: military quarters of midshipmen and junior officers on a British warship
military quarters: living quarters for personnel on a military post

gun room (noun)	military quarters (noun)
military quarters of midshipmen and junior officers on a British warship	living quarters for personnel on a military post