urban center vs Novosibirsk

urban center and Novosibirsk both are nouns.

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

urban center (noun)	Novosibirsk (noun)
a large and densely populated urban area; may include several independent administrative districts	a city in the Asian part of Russia on the Ob river; largest city in Siberia