building vs anteroom

building and anteroom both are nouns.

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

building (noun)	anteroom (noun)
the act of constructing something	a large entrance or reception room or area
the commercial activity involved in repairing old structures or constructing new ones
a structure that has a roof and walls and stands more or less permanently in one place
the occupants of a building