A term used for when a person is in a good position for something and another person tries to occupy the same position making it less good for the first person. Usually used while fishing, hunting, sniping, and "camping" (video games). The second person may be subtracting/ attempting to subtract from the fish caught, animals shot, or other players to kill. The second person may also be giving away the first persons position (camping).
Guy 1- Man, I didn't catch any fish/ shoot any deer/ get any kills/ because that retard spot-fucked me the whole time!
Guy 2- Yeah, he spot-fucked me too and scared off the fish/ deer/ blew my cover.