Sardis vs urban center

Sardis and urban center both are nouns.

Word	Noun	Adjective	Verb	Adverb
Sardis	Yes	No	No	No
urban center	Yes	No	No	No

Sardis (noun)	urban center (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	a large and densely populated urban area; may include several independent administrative districts