What countries language is not related to any other in the world?

There's no language in the world that's completely unrelated to any other. Linguists believe that all languages, even those seemingly very different, ultimately trace back to a common ancestor, likely spoken tens of thousands of years ago.

This common ancestor is called Proto-World, and although we don't have any direct evidence of it, linguists have been able to reconstruct parts of it by analyzing the similarities and differences between existing languages.

However, there are languages that are considered language isolates, meaning they have no known genetic relationship to any other living language. Here are a few examples:

* Basque: Spoken in the Pyrenees region of Spain and France, Basque is considered a language isolate and is believed to be the last surviving member of a once larger language family.

* Burushaski: Spoken in northern Pakistan, Burushaski is another language isolate with no known genetic relationship to any other language.

* Ainu: Originally spoken in Japan and parts of Russia, Ainu is considered a language isolate, though some linguists propose it might be distantly related to other languages in Northeast Asia.

It's important to note that even though these languages are classified as isolates, there's always the possibility of discovering new connections or evidence that could change our understanding of their relationships. The study of language families and relationships is ongoing, and new discoveries are made all the time.