A hand of less value than a pair (e.g. if you miss a straight, you have a busted straight).
A drawing hand that failed to improve(ex. "busted flush").
(1) A worthless hand (Bust). (2) A hand that failed to fill a straight or a flush on the draw.
A hand that doesn't even have a Pair (if you missed a Flush, you have a Busted Flush).