urban center vs Mwanza

urban center and Mwanza both are nouns.

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

urban center (noun)	Mwanza (noun)
a large and densely populated urban area; may include several independent administrative districts	a city in northern Tanzania on Lake Victoria