urban center vs Christchurch

urban center and Christchurch both are nouns.

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

urban center (noun)	Christchurch (noun)
a large and densely populated urban area; may include several independent administrative districts	industrial city at the center of a rich agricultural region