Oakland vs city

Oakland and city both are nouns.

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

Oakland (noun)	city (noun)
a city in western California on San Francisco Bay opposite San Francisco; primarily and industrial urban center	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