Calcutta vs metropolis

Calcutta and metropolis both are nouns.

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

Calcutta (noun)	metropolis (noun)
the largest city in India and one of the largest cities in the world; located in eastern India; suffers from poverty and overcrowding	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts