Brownsville vs metropolis

Brownsville and metropolis both are nouns.

Word	Noun	Adjective	Verb	Adverb
Brownsville	Yes	No	No	No
metropolis	Yes	No	No	No

Brownsville (noun)	metropolis (noun)
a city in southern Texas on the Rio Grande near its mouth into the Gulf of Mexico; has a channel that accommodates oceangoing ships	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts