Indo-European is most commonly referred to by many – usually non-Indo-European – linguists as the hypothetical common ancestor of the Indo-European languages. Also, people usually refer to other languages or language families without written remains as hypothesis. We could talk, then, about the hypothetical Indo-Uralic, Eurasian, Ural-Altaic, Proto-Pontic or Nostratic languages, for example.
On the other hand, there are some languages, like Minoan – already mentioned in the previous post -, which aren’t officially hypothetical. I guess that’s because we have some written remains (still undeciphered) of a probable language system, supposedly related to Eteocretan, a younger language … Read the rest “About the 'hypothetical' Proto-Indo-European language”