city vs Kolkata

city and Kolkata both are nouns.

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

city (noun)	Kolkata (noun)
people living in a large densely populated municipality	the largest city in India and one of the largest cities in the world; located in eastern India; suffers from poverty and overcrowding
a large and densely populated urban area; may include several independent administrative districts
an incorporated administrative district established by state charter