closet vs room

closet and room both are nouns.

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

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

closet (noun)	room (noun)
a small private room for study or prayer	an area within a building enclosed by walls and floor and ceiling
a toilet in Britain	the people who are present in a room
a tall piece of furniture that provides storage space for clothes; has a door and rails or hooks for hanging clothes	space for movement
a small room (or recess) or cabinet used for storage space	opportunity for

closet (verb)	room (verb)
confine to a small space, as for intensive work	live and take one's meals at or in