cardroom vs room

cardroom and room both are nouns.

Word	Noun	Adjective	Verb	Adverb
cardroom	Yes	No	No	No
room	Yes	No	Yes	No

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

cardroom (noun)	room (noun)
a room for gambling on card games	an area within a building enclosed by walls and floor and ceiling
	the people who are present in a room
	space for movement
	opportunity for

cardroom (verb)	room (verb)
	live and take one's meals at or in