metropolis vs Nantes

metropolis and Nantes both are nouns.

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

metropolis (noun)	Nantes (noun)
people living in a large densely populated municipality	a port city in western France on the Loire estuary
a large and densely populated urban area; may include several independent administrative districts