Greensboro vs metropolis

Greensboro and metropolis both are nouns.

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

Greensboro (noun)	metropolis (noun)
a city of north central North Carolina, the city with the third-largest population in North Carolina	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts