Western Siouan languages
The Western Siouan languages, also called Siouan proper or simply Siouan, are a large language family native to North America. They are closely related to the Catawban languages, sometimes called Eastern Siouan, and together with them constitute the Siouan (Siouan–Catawban) language family.
Lakota people
The Lakota (pronounced , Lakota language: Lakȟóta) are a Native American tribe. Also known as the Teton Sioux (from "Thítȟuŋwaŋ"), they are one of the three Sioux tribes of Plains. Their current lands are in North and South Dakota. They speak "Lakȟótiyapi"—the Lakota language, the westernmost of three closely related languages that belong to the Siouan language family.