| Noun | 1. |  Siouan - a member of a group of North American Indian peoples who spoke a Siouan language and who ranged from Lake Michigan to the Rocky Mountains Buffalo Indian, Plains Indian - a member of one of the tribes of American Indians who lived a nomadic life following the buffalo in the Great Plains of North America Biloxi - a member of the Siouan people of southeastern Mississippi Catawba - a member of the Siouan people formerly living in the Carolinas Crow - a member of the Siouan people formerly living in eastern Montana Dakota - a member of the Siouan people of the northern Mississippi valley; commonly called the Sioux Dhegiha - any member of a Siouan people speaking one of the Dhegiha languages Gros Ventre, Hidatsa - a member of the Sioux people formerly inhabiting an area along the Missouri river in western North Dakota Missouri - a member of the Siouan people formerly inhabiting the valley of the Missouri river in Missouri Ofo - a member of the Siouan people living in the Yazoo river valley in Mississippi Oto, Otoe - a member of the Siouan people inhabiting the valleys of the Platte and Missouri rivers in Nebraska Lakota, Teton, Teton Dakota, Teton Sioux - a member of the large western branch of Sioux people which was made up of several groups that lived on the plains Tutelo - a member of the Siouan people of Virginia and North Carolina Winnebago - a member of the Siouan-speaking people formerly living in eastern Wisconsin south of Green Bay; ally of the Menomini and enemy of the Fox and Sauk people | 
| 2. | Siouan - a family of North American Indian languages spoken by the Sioux American-Indian language, Amerind, Amerindian language, American Indian, Indian - any of the languages spoken by Amerindians Biloxi - the Siouan language spoken by the Biloxi Catawba - the Siouan language spoken by the Catawba Chiwere - the Siouan language spoken by the Iowa and Oto and Missouri Crow - a Siouan language spoken by the Crow Dakota - the Siouan language spoken by the Dakota Dhegiha - a branch of the Siouan languages Gros Ventre, Hidatsa - a Siouan language spoken by the Hidatsa Hunkpapa - a Siouan language spoken by the Hunkpapa Ofo - a Siouan language spoken by the Ofo Santee - the Siouan language spoken by the Santee Tutelo - the Siouan language spoken by the Tutelo Winnebago - the Siouan language spoken by the Winnebago | |
| Adj. | 1. | Siouan - of or relating to the Sioux people or their language and culture |