urban center vs Omiya

urban center and Omiya both are nouns.

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

urban center (noun)	Omiya (noun)
a large and densely populated urban area; may include several independent administrative districts	a city of east central Honshu; a suburb of Tokyo