Sardis vs metropolis

Sardis and metropolis both are nouns.

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

Sardis (noun)	metropolis (noun)
an ancient Greek city located in the western part of what is now modern Turkey; as the capital of Lydia it was the cultural center of Asia Minor; destroyed by Tamerlane in 1402	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts