1) Gros ventre 2) Siouan 3) Sioux 
The Hidatsa are a Siouan people. Today Hidatsa are enrolled in the federally recognized Three Affiliated Tribes of the Fort Berthold Reservation in North Dakota. Their language is related to that of the Crow, and they are sometimes considered a parent tribe to the modern Crow in Montana. Occasionally they have also been confused with the Gros Vent...
North American Indians of the Plains who once lived in semipermanent villages on the upper Missouri River between the Heart and the Little Missouri ... [4 related articles]
[n] - a member of the Sioux people formerly inhabiting an area along the Missouri river in western North Dakota 2. [n] - a Siouan language spoken by the Hidatsa people
Gros Ventre noun a Siouan language spoken by the Hidatsa
a member of a Siouan people dwelling on the Missouri River. · the Siouan language of the Hidatsa tribe.