Mexico vs Sierra Madre Occidental

Mexico and Sierra Madre Occidental both are nouns.

Word	Noun	Adjective	Verb	Adverb
Mexico	Yes	No	No	No
Sierra Madre Occidental	Yes	No	No	No

Mexico (noun)	Sierra Madre Occidental (noun)
a republic in southern North America; became independent from Spain in 1810	a mountain range in northwestern Mexico that runs south from Arizona parallel to the Pacific coastline