The Collaborative International Dictionary of English v.0.48:

Shoshones \Sho*sho"nes\, n. pl.; sing. Shoshone. (Ethnol.)
   A linguistic family or stock of North American Indians,
   comprising many tribes, which extends from Montana and Idaho
   into Mexico. In a restricted sense the name is applied
   especially to the Snakes, the most northern of the tribes.
   [1913 Webster]