Kaluga vs city

Kaluga and city both are nouns.

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

Kaluga (noun)	city (noun)
a city of central Russia to the south of Moscow	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