urban center vs Joao Pessoa

urban center and Joao Pessoa both are nouns.

Word	Noun	Adjective	Verb	Adverb
urban center	Yes	No	No	No
Joao Pessoa	Yes	No	No	No

urban center (noun)	Joao Pessoa (noun)
a large and densely populated urban area; may include several independent administrative districts	a city in northeastern Brazil near the Atlantic Ocean to the north of Recife