Kambiwá Cambioá is an extinct unclassified language

Unclassified language

Unclassified languages are languages whose genetic affiliation has not been established by means of historical linguistics. If this state of affairs continues after significant study of the language and efforts to relate it to other languages, as in the case of Basque, it is termed a language...

of Brazil. A couple dozen words were collected from two people in the 1960s, but by that time no-one spoke the language any longer. Apart from two apparent borrowings, none of the words are relatable to known languages. Loukotka (1968) characterized the language as unclassifiable due to lack of data.