metropolis vs Naha City

metropolis and Naha City both are nouns.

Word	Noun	Adjective	Verb	Adverb
metropolis	Yes	No	No	No
Naha City	Yes	No	No	No

metropolis (noun)	Naha City (noun)
people living in a large densely populated municipality	the chief city in the Ryukyu Islands
a large and densely populated urban area; may include several independent administrative districts