entrance hall vs anteroom

entrance hall and anteroom both are nouns.

Word	Noun	Adjective	Verb	Adverb
entrance hall	Yes	No	No	No
anteroom	Yes	No	No	No

As nouns, entrance hall and anteroom are synonyms defined as:

Other synonyms of entrance hall include antechamber, foyer, hall, lobby, vestibule.

entrance hall (noun)	anteroom (noun)
a large entrance or reception room or area	a large entrance or reception room or area