octoroon

n. octaroon, offensive term for a person of mixed race who has one-eighth Black ancestry

Quadroon, octoroon and, more rarely, quintroon were historically racial categories of hypodescent used in Latin America and parts of the 19th century Southern United States, particularly Louisiana. The terms were also used in Australia to refer to people of mixed Aboriginal and European ancestry.Quadroon is someone of one-quarter black ancestry. A quadroon has a biracial parent (black and white) and one white parent. In other words, the person has one black grandparent and three white grandparents.Octoroon means a person of fourth-generation black ancestry. An octoroon has one parent who is a quadroon and one white parent. In other words, the person has one black great-grandparent and seven white great-grandparents.
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(n.)
The offspring of a quadroon and a white person; a mestee.
  

Noun
1. an offspring of a Quadroon and a White parent; a person who is one-eighth Black
(hypernym) mixed-blood