city vs Mannheim

city and Mannheim both are nouns.

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

city (noun)	Mannheim (noun)
people living in a large densely populated municipality	a city in southwestern Germany at the confluence of the Rhine and Neckar rivers
a large and densely populated urban area; may include several independent administrative districts
an incorporated administrative district established by state charter