The lovechild of the affirmative and (sometimes exuberantly) enthused 'yay' and the elongated 'yeeaaah(idon'treallygiveafuckbutletsjustbothpretendido)', used when one cannot decide just how much of a fuck not to give about a piece of information and does not bother to hide that notion from their dialog partner.
Anthony: I got 11$ for the cans I have been collecting over the past 6 month.

Adam: Yuay.
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