urban center vs Hong Kong

urban center and Hong Kong both are nouns.

Word	Noun	Adjective	Verb	Adverb
urban center	Yes	No	No	No
Hong Kong	Yes	No	No	No

urban center (noun)	Hong Kong (noun)
a large and densely populated urban area; may include several independent administrative districts	formerly a Crown Colony on the coast of southern China in Guangdong province; leased by China to Britain in 1842 and returned in 1997; one of the world's leading commercial centers