Caucasus vs geographical region

Caucasus and geographical region both are nouns.

Word	Noun	Adjective	Verb	Adverb
Caucasus	Yes	No	No	No
geographical region	Yes	No	No	No

Caucasus (noun)	geographical region (noun)
a large region between the Black and Caspian seas that contains the Caucasus Mountains; oil is its major resource	a demarcated area of the Earth
the mountain range in Caucasia between the Black Sea and the Caspian Sea that forms part of the traditional border between Europe and Asia