Guachí (Wachí) is an extinct, apparently Guaicuruan language of Argentina.
It is usually classified as one of the Guaicuruan languages, but the data is insufficient to demonstrate that.
[1] Guachi is known only from 145 words collected by Francis de Castelnau from March to early April 1845 in the Miranda area of Argentina.
[2][3] Viegas Barros (2004) proposes that Guachi, as well as Payaguá, may be a Macro-Guaicurúan language.
[4] Guachi words and affixes listed in Viegas Barros (2004):[3]