room vs building

room and building both are nouns.

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

room (noun)	building (noun)
an area within a building enclosed by walls and floor and ceiling	the act of constructing something
the people who are present in a room	the commercial activity involved in repairing old structures or constructing new ones
space for movement	a structure that has a roof and walls and stands more or less permanently in one place
opportunity for	the occupants of a building

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