equicide noun2 •The killing of a horse.But had Mary shot Pond Pen, the things that alleged race horse had done to her would certainly have caused any fair judge to pronounce Pond Pen’s violent passing justifiable equicide. — 1951 •One who or that which kills a horse.One Mr. Shrock, who was pursuing the Taylor brothers, managed to shoot his own horse, through and through. The crowd made the equicide stand by the dead beast and be photographed. — 1894 formsequicides