also: かなめん
noun
iron mask (samurai)
Historical term for a protective iron mask worn by samurai.
戦国時代の武士は、顔を守るために鉄面を着用した。
Samurai in the Warring States period wore iron masks to protect their faces.
Compound of 鉄 (iron) and 面 (mask/face). The exact historical origin is uncertain, but it refers to a piece of samurai armor.