canteen vs recreation room

canteen and recreation room both are nouns.

Word	Noun	Adjective	Verb	Adverb
canteen	Yes	No	No	No
recreation room	Yes	No	No	No

As nouns, recreation room is a hypernym of canteen; that is, recreation room is a word with a broader meaning than canteen:

Other hypernyms of canteen include rec room.

canteen (noun)	recreation room (noun)
a flask for carrying water; used by soldiers or travelers	a room equipped for informal entertaining
restaurant in a factory; where workers can eat
a recreation room in an institution
a restaurant outside; often for soldiers or policemen
sells food and personal items to personnel at an institution or school or camp etc.