premacheer ejaculation
noun: a loud cheer ejaculated loudly and involuntarily during a sporting event when one thinks his or her team gained some ground, when it really was a play that favored the other team.
Sitting in the Brazil section of the futbol staduim, Jose emitted a premacheer ejaculation thinking his team's goalie had made the save, when the ball had actually rolled in. The other Brazil fans beat him up for his mistake.