Kolkata vs city

Kolkata and city both are nouns.

Word	Noun	Adjective	Verb	Adverb
Kolkata	Yes	No	No	No
city	Yes	No	No	No

Kolkata (noun)	city (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
	an incorporated administrative district established by state charter