Luluabourg vs metropolis

Luluabourg and metropolis both are nouns.

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

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