Nova Lisboa vs metropolis

Nova Lisboa and metropolis both are nouns.

Word	Noun	Adjective	Verb	Adverb
Nova Lisboa	Yes	No	No	No
metropolis	Yes	No	No	No

Nova Lisboa (noun)	metropolis (noun)
a city in the mountains in western Angola	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts