Siouan languages
Siouan languages can be grouped into the Western Siouan languages and Catawban languages. The Western Siouan languages can be divided into Missouri River languages (such as Crow and Hidatsa), Mandan, Mississippi River languages (such as Dakotan, Chiwere-Winnebago, and Dhegihan languages), and Ohio Valley Siouan branches. The Catawban languages consist only of Catawban and Woccon.
Mandan
The English name "Mandan" is derived from the French-Canadian explorer Pierre Gaultier, Sieur de la Verendrye, who in 1738 heard it as "Mantannes" from his Assiniboine guides, which call the Mandan "Mayádąna". He had previously heard the earth lodge peoples referred to by the Cree as "Ouachipouennes", "the Sioux who go underground". The Assiniboine are Siouan speakers. Nearby Siouan speakers had exonyms similar to "Mantannes" in their languages, for instance, Teton "Miwáthaŋni" or "Miwátąni", Yanktonai "Miwátani", Yankton "Mawátani" or "Mąwátanį", Dakota "Mawátąna" or "Mawátadą", etc.