rumpus room vs rec room

rumpus room and rec room both are nouns.

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

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

rumpus room: a recreation room for noisy activities (parties or children's play etc)
rec room: a room equipped for informal entertaining

Other hypernyms of rumpus room include recreation room.

rumpus room (noun)	rec room (noun)
a recreation room for noisy activities (parties or children's play etc)	a room equipped for informal entertaining