urban center vs Liege

urban center and Liege both are nouns.

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

urban center (noun)	Liege (noun)
a large and densely populated urban area; may include several independent administrative districts	city in eastern Belgium; largest French-speaking city in Belgium