Ostrava vs city

Ostrava and city both are nouns.

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

Ostrava (noun)	city (noun)
an industrial city in northwestern Czech Republic in the Moravian lowlands; located in the coal mining area of Silesia	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