[1] : The Collaborative International Dictionary of English v.0.48

quadroon \quadroon"\, n. f. quarteron, or sp. cuarteron. see
   quarter a fourth part, and cf. quarteron.
   the offspring of a mulatto and a white person; a person
   quarter-blooded. written also quarteron, quarteroon, and
   quateron.
   1913 webster
see also:
quarter quarteron quarteron quarteroon quateron 

[2] : WordNet (r) 2.0

quadroon
     n : an offspring of a mulatto and a white parent; a person who
         is one-quarter black

[3] : Moby Thesaurus II by Grady Ward, 1.0

35 moby thesaurus words for "quadroon":
   cape colored, eurasian, cattalo, citrange, cross, crossbreed,
   griffe, half blood, half-bred, half-breed, half-caste, high yellow,
   hinny, hybrid, ladino, liger, mestee, mestiza, mestizo, metis,
   metisse, mixblood, mixed-blood, mongrel, mulatto, mule, mustee,
   octoroon, plumcot, quintroon, sambo, tangelo, tigon, zebrass,
   zebrule

[4] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

quadroon. a person who is descended from a white person, and another person 
who has an equal mixture of the european and african blood. 2 bailey, 558. 
vide mulatto. 

Quadroon >> Q Words
Quadroon, definition of term: Quadroon
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