urban center vs Memphis

urban center and Memphis both are nouns.

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

urban center (noun)	Memphis (noun)
a large and densely populated urban area; may include several independent administrative districts	largest city of Tennessee; located in southwestern Tennessee on bluffs overlooking the Mississippi River
	an ancient city of Egypt on the Nile (south of Cairo)