Caucasic vs Caucasus

Caucasic is not a noun while Caucasus is a noun.

Word	Noun	Adjective	Verb	Adverb
Caucasic	No	Yes	No	No
Caucasus	Yes	No	No	No

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

Caucasic (adjective)	Caucasus (adjective)
of or relating to the geographical region of Caucasia