Bologna vs metropolis

Bologna and metropolis both are nouns.

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

Bologna (noun)	metropolis (noun)
the capital of Emilia-Romagna; located in northern Italy to the east of the Apennines	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts