city vs San Sebastian

city and San Sebastian both are nouns.

Word	Noun	Adjective	Verb	Adverb
city	Yes	No	No	No
San Sebastian	Yes	No	No	No

city (noun)	San Sebastian (noun)
people living in a large densely populated municipality	a city in northern Spain on the Bay of Biscay near the French border; a fashionable seaside resort
a large and densely populated urban area; may include several independent administrative districts
an incorporated administrative district established by state charter