urban center vs Atlantic City

urban center and Atlantic City both are nouns.

Word	Noun	Adjective	Verb	Adverb
urban center	Yes	No	No	No
Atlantic City	Yes	No	No	No

urban center (noun)	Atlantic City (noun)
a large and densely populated urban area; may include several independent administrative districts	a city on the Atlantic shore in southeastern New Jersey; a resort and gambling center