A spotlight used for poaching animals, esp deer. The reference is to instead of using dogs to chase the animal in question, you "spotlight" it, and it freezes, long enough for you to shoot it, usually from your car.
"Waitin in the front yard sittin on a log, single shot rifle and a one eyed dog, yonder come my kinfolk in the moonlight, Lousiana Saturday night." -from the Mel Mcdaniels song "Louisiana Saturday Night."
by Joe VII March 27, 2010