metropolis vs Northampton

metropolis and Northampton both are nouns.

Word	Noun	Adjective	Verb	Adverb
metropolis	Yes	No	No	No
Northampton	Yes	No	No	No

metropolis (noun)	Northampton (noun)
people living in a large densely populated municipality	the principal city of Northamptonshire
a large and densely populated urban area; may include several independent administrative districts