Wakizashi

A wakizashi is a shorter samurai sword, often used as a combination with its larger counterpart the katana.

The katana and wakizashi (together called a daishō) are used simultaneously during the Two Heavens technique. Otherwise, the wakizashi was seldom used in combat. Rather, it was used to cut off the heads of enemies (which samurai often took as trophies) and in Seppuku, a ritual suicide done by the samurai.