Dialect:

By the definition most commonly used by linguists, any linguistic variety can be considered a "dialect" of some language—"everybody speaks a dialect". According to that interpretation, the criteria above merely serve to distinguish whether two varieties are dialects of the same language or dialects of different languages.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". According to the least used definition, what does everyone speak?
unanswerable