Yangho language

Spurious languages are languages that have been reported as existing in reputable works, while other research has reported that the language in question did not exist. Some spurious languages have been proven to not exist. Others have very little evidence supporting their existence, and have been dismissed in later scholarship. Others still are of uncertain existence due to limited research.

Below is a sampling of languages that have been claimed to exist in reputable sources but have subsequently been disproved or challenged. In some cases a purported language is tracked down and turns out to be another, known language. This is common when language varieties are named after places or ethnicities.

Some alleged languages turn out to be hoaxes, such as the Kukurá language of Brazil or the Taensa language of Louisiana. Others are honest errors that persist in the literature despite being corrected by the original authors; an example of this is ', the name given in 1892 to two Colonial word lists, one of Tlingit and one of a Salishan language, that were mistakenly listed as Patagonian. The error was corrected three times that year, but nonetheless "Hongote" was still listed as a Patagonian language a century later in Greenberg (1987).

In the case of New Guinea, one of the most linguistically diverse areas on Earth, some spurious languages are simply the names of language surveys that the data was published under. Examples are '', Kia, , '', listed as Indo-Pacific languages in Ruhlen 1987; these are actually rivers that gave their names to language surveys in the Greater Awyu languages and Ok languages of New Guinea.

Dubious languages

Dubious languages are those whose existence is uncertain. They include:
* Oropom ( Uganda)
* Nemadi (Mauritania)
* Rer Bare ( Ethiopia) – extinct, if it ever existed
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