Sakabato

Sakabato (逆刃刀, reverse-edged sword) is a fictional type of Japanese sword. On the normal katana, the outward curved side of the blade is sharpened, while the inward curved side of the blade is blunt. In contrast, the sakabato is made so that the cutting edge is on the side that curves inward. Although functional sakabato are currently being produced for purchase by collectors and fans, there is no record of them ever having been used historically in Japan. There is also no school of swordsmanship existing that employs them. However, historical use of "reverse-blade" weapons is evident from samples held at the Deoksu Royal Palace Museum in Korea. Because Japan at one time invaded Korea, the possibility remains open that a sakabato was developed based on Korean examples. However, as aforementioned, no historical record nor archaeological evidence currently exists to support such a theory. Some Tanto (Knives) have been found that have "reversed blades". These are labeled kubikiri, sometimes translated as "head cutter" or "doctor's knife".