urban center vs Chittagong

urban center and Chittagong both are nouns.

Word	Noun	Adjective	Verb	Adverb
urban center	Yes	No	No	No
Chittagong	Yes	No	No	No

urban center (noun)	Chittagong (noun)
a large and densely populated urban area; may include several independent administrative districts	a port city and industrial center in southeastern Bangladesh on the Bay of Bengal