White race vs Caucasian

White race and Caucasian both are nouns.

Word	Noun	Adjective	Verb	Adverb
White race	Yes	No	No	No
Caucasian	Yes	Yes	No	No

White race (noun)	Caucasian (noun)
a light-skinned race	a number of languages spoken in the Caucasus that are unrelated to languages spoken elsewhere
	a person of European descent with a light-skinned or pale complexion

White race (adjective)	Caucasian (adjective)
	of or relating to the geographical region of Caucasia
	of or relating to Caucasian people