Plateau Sign Language, or Old Plateau Sign Language, is a poorly attested sign language historically used in British Columbia. It is not clear if it was a regional variant of Plains Standard Sign Language, the contact pidgin of the Great Plains, or a separate trade language indigenous to the Columbian Plateau. The Crow Nation introduced Plains Standard, which replaced Plateau Sign among the eastern nations that used it (the Coeur d’Alene, Sanpoil, Okanagan, Thompson, Lakes, Shuswap, and Coleville), with western nations shifting instead to Chinook Jargon.
Further reading [ edit ]
Sign languages by region
American Sign Language
Extinct sign languages
Sign-language names reflect the region of origin. Natural sign languages are not related to the spoken language used in the same region. For example, French Sign Language originated in France, but is not related to French.