Tehuelche (Aoniken, Inaquen, Gunua-Kena, Gununa-Kena) is a Chon language of Patagonia. Its speakers were nomadic hunters who occupied territory in present-day Chile, north of Tierra del Fuego and south of the Mapuche people. It is also known as Aonikenk or Aonek'o 'ajen.
The decline of the language started with the Araucanization of Patagonia, when many Tehuelche tribes adopted Mapudungun as their main language. While being quite separate from each other, the Tehuelche were considerably influenced by these two other languages and cultures. This allowed the transference of morpho-syntactical elements into Tehuelche. During the 19th and 20th centuries, Spanish became the dominant language as Argentina and Chile gained independence, and Spanish-speaking settlers took possession of Patagonia.