Santa Cruz de la Sierra vs metropolis

Santa Cruz de la Sierra and metropolis both are nouns.

Word	Noun	Adjective	Verb	Adverb
Santa Cruz de la Sierra	Yes	No	No	No
metropolis	Yes	No	No	No

Santa Cruz de la Sierra (noun)	metropolis (noun)
a city in central Bolivia	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts