Bahia Blanca vs urban center

Bahia Blanca and urban center both are nouns.

Word	Noun	Adjective	Verb	Adverb
Bahia Blanca	Yes	No	No	No
urban center	Yes	No	No	No

Bahia Blanca (noun)	urban center (noun)
a port city in eastern Argentina to the southwest of Buenos Aires on an inlet of the Atlantic Ocean	a large and densely populated urban area; may include several independent administrative districts