Shinai

Shinai (竹刀^?) is a weapon used for practice and competition in kendo representing a Japanese sword. Shinai are also used in other martial arts, but may be styled differently from kendo shinai, and represented with different characters.

Shinai should not be confused with bokken, or wooden swords.

The earliest use of a bamboo weapon to train with instead of a sword is credited to Kamiizumi Nobutsuna (1508-1572?) of the Shinkage-ryū. The modern shinai, with four slats of bamboo, is generally credited to Nakanishi Chuzo Tsugutate (died 1801) of Nakanishi-ha Ittō-ryū. The shinai was developed in an effort to reduce the number of practitioners being seriously injured during practice, making a practice weapon that was less dangerous than bokutō (木刀^?), the hard wooden swords they were previously using. This is also the motivation behind the development of bōgu (防具^?), the armour that protects the kendoka.

The word "shinai" is derived from the verb shinau (撓う^?), meaning "to bend, to flex", and was originally short for shinai-take (flexible bamboo). Shinai is written with the kanji 竹刀, meaning "bamboo sword", and is an irregular kanji reading.

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