Milan vs metropolis

Milan and metropolis both are nouns.

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

Milan (noun)	metropolis (noun)
the capital of Lombardy in northern Italy; has been an international center of trade and industry since the Middle Ages	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts