Sao Louis vs urban center

Sao Louis and urban center both are nouns.

Word	Noun	Adjective	Verb	Adverb
Sao Louis	Yes	No	No	No
urban center	Yes	No	No	No

Sao Louis (noun)	urban center (noun)
a city on an offshore island in northeast Brazil	a large and densely populated urban area; may include several independent administrative districts