Bologna vs urban center

Bologna and urban center both are nouns.

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

Bologna (noun)	urban center (noun)
the capital of Emilia-Romagna; located in northern Italy to the east of the Apennines	a large and densely populated urban area; may include several independent administrative districts