Pisa vs metropolis

Pisa and metropolis both are nouns.

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

Pisa (noun)	metropolis (noun)
a city in Tuscany; site of the famous Leaning Tower	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts