Source : Webster's Revised Unabridged Dictionary (1913)

White person \White person\
   A person of the Caucasian race (--6 Fed. Rep. 256).

   Note: In the time of slavery in the United States white
         person was generally construed as a person without
         admixture of colored blood. In various statutes and
         decisions in different States since 1865 white person
         is construed as in effect: one not having any negro
         blood (Ark., Okla.); one having less than one eighth of
         negro blood (Ala., Fla., Ga., Ind., Ky., Md., Minn.,
         Miss., Mo., N.C., S.C., Tenn., Tex.); one having less
         than one fourth (Mich., Neb., Ore., Va.); one having
         less than one half (Ohio).

Source : WordNet®

white person
     n : a member of the Caucasoid race [syn: {White}, {Caucasian}]