rec room vs family room

rec room and family room both are nouns.

Word	Noun	Adjective	Verb	Adverb
rec room	Yes	No	No	No
family room	Yes	No	No	No

As nouns, family room is a hyponym of rec room; that is, family room is a word with a more specific, narrower meaning than rec room:

Other hyponyms of rec room include canteen, game room, playroom, rumpus room.

rec room (noun)	family room (noun)
a room equipped for informal entertaining	a recreation room in a private house