Wichí Lhamtés Güisnay

Wichí Lhamtés Güisnay or Wiznay is a Wichí language. Wichí Lhamtés Güisnay had an estimated 15,000 speakers in 1999 in Argentina. The language is centered in the Pilcomayo River region. Other names for the language include Güisnay, Mataco, Mataco Güisnay, Mataco Pilcomayo, and Wichí Lhamtés. A grammar book has been written for the language.

The Wichí languages are predominantly suffixing and polysynthetic; verbal words have between 2 and 15 morphemes. Alienable and inalienable possession is distinguished. The phonological inventory is large, with simple, glottalized and aspirated stops and sonorants. The number of vowels varies with the language (five or six).