one-drop rule

[ wuhn-drop-rool ]

noun

U.S. History. a social classification, codified in law in some states during the 20th century, that identifies biracial or multiracial individuals as Black if they have any known Black African ancestry, even from a Black ancestor many generations removed.

Origin of one-drop rule

First recorded in 1920–25 (as one-drop law); from the ideology that “one drop” of Black African blood made a person Black

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