Stumped is a method of dismissing a batter in cricket, in which the wicket-keeper puts down the wicket of the striker while the striker is out of their ground.[1] It is governed by Law 39 of the Laws of Cricket.[1]
Being "out of their ground" means no part of the batter's body, equipment or bat is touching the ground behind the crease.
Stumped is a special case of run out, but a stumping can only be affected by the wicket-keeper without the intervention of another fielder, when the striker is not attempting a run, and the ball must not be a no-ball. If the criteria for both stumped and run out are met, then the dismissal will be recorded as a stumping and credited to the bowler and wicket-keeper.[2]
As always in cricket, one of the fielding team must appeal for the wicket by asking the umpires. It is the striker's end umpire who adjudicates all stumpings, and all run-out appeals at the striker's end.