Origin and Etymology of sioux
American French, short for Nadouessioux, from Ojibwa na·towe·ssiw-
First Known Use: 1762
SIOUX Defined for English Language Learners
Definition of Sioux for English Language Learners
: a member of a Native American people originally from the north central U.S.
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Britannica.com: Encyclopedia article about Sioux
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