urban center vs Hannover

urban center and Hannover both are nouns.

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

urban center (noun)	Hannover (noun)
a large and densely populated urban area; may include several independent administrative districts	a port city in northwestern Germany; formerly a member of the Hanseatic League