urban center vs Merida

urban center and Merida both are nouns.

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

urban center (noun)	Merida (noun)
a large and densely populated urban area; may include several independent administrative districts	the capital of the Mexican state of Yucatan