Chiburi

Chiburui (血振るい), also called chiburi,[1] is the process by which one symbolically removes blood from a sword blade.

In the Japanese martial art of iaidō, this is done before nōtō or placing the blade back into the scabbard (known as saya).

[2] In films set in feudal Japan, such as Zatoichi, chiburi is usually performed by swordsmen after the killing of an opponent.

However, chiburi is incorrectly portrayed as a simple swipe that completely removes all of the blood.

In reality, the sword needs to be thoroughly wiped with a cloth as there would still be enough blood on the blade to cause rusting.