Tonbo-Giri, literally meaning "Dragonfly Cutter" (蜻蛉切), was the spear of the legendary samurai Honda Tadakatsu, who served Tokugawa Ieyasu during the Warring States period of Japanese History (early 16th to 17th century). This spear was allegedly so sharp that a dragonfly once landed on it and was instantly sliced in half.