Gunbai

The gunbai (軍配^?, short for 軍配団扇 gunbai-uchiwa) military leader's fan (in old Japan); umpire's fan (in sumo wrestling) is a type of Japanese war fan.

Gunbai, from the Sino-Japanese roots meaning "military-apportioned [fan]", were a specialized form of fan used by samurai officers in Japan to communicate commands to their troops. Unlike regular fans, gunbai were solid, not folding, and usually made of wood, wood covered with metal, or solid metal.

It is also a key accessory of a gyōji in professional sumo. The main use is at the end of a bout, when the gyoji decides the victor and points the gunbai to either the east or west position (each wrestler is assigned to start from either the east or west position each tournament day). Reflecting this, the gyōji's decision itself is often informally referred to as a "gunbai". If this is called into question and the judges hold a consultation, a decision to uphold the gyōji's judgement is announced as gunbai-dōri (軍配通り), literally "according to the gunbai", while a decision to overturn it is gunbai-sashichigae (軍配差し違え), literally "gunbai mispointed."

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