urban center vs Rosario

urban center and Rosario both are nouns.

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

urban center (noun)	Rosario (noun)
a large and densely populated urban area; may include several independent administrative districts	a port city on the Parana River in eastern central Argentina