Luluabourg vs urban center

Luluabourg and urban center both are nouns.

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

Luluabourg (noun)	urban center (noun)
a city in southwestern Congo; former name (until 1966) was Luluabourg	a large and densely populated urban area; may include several independent administrative districts