a trick

When someone attemps or has recently cheated you out of something (money, favors, clothes, etc) or cheated on you, or is trying to be sneaky and underhanded behind your back, and you find out either before the act is done or right after the act is done. You then rectify the situation immediatley or set it up where you will get payback in a major way later. Can be as small as someone snitching on you at the job or giving you a sob story to borrow money for something important that reaaly isn't, to your mate cheating on you or someone setting you up to be arrested or robbed