The
plural form of
y'all. Yes, such a thing is possible.
In Southern Drawl, "you" is the second person singular pronoun, and "y'all" is the second person plural -- but only when referring to a relatively small group. A large group requires the superplural "all y'all". Similar to the way "hair" is pluralized to "hairs" for a few or "hair" for a whole head of it.