Katsu (Zen)

Katsu (Japanese: ; Cantonese:  hot3 , Pinyin: hè, Wade-Giles: ho) is a shout that is described in Chán and Zen Buddhism encounter-stories, to expose the enlightened state (Japanese: satori) of the Zen-master, and/or to induce initial enlightenment experience in a student. The shout is also sometimes used in the East Asian martial arts for a variety of purposes; in this context, katsu is very similar to the shout kiai.

The word in Chinese means literally "to yell" or "to shout". In Japanese it has also developed the meaning of "", "to scold", and "hoarse".

In the context of Chan and Zen practice, the word is not generally used in its literal meaning(s), but rather — much as with the martial arts shout of kiai — as fundamentally a means of focusing energy. When the Chan and Zen practice of the katsu first emerged in Jiangxi province in the south of Tang dynasty China in the 8th century CE, the word was pronounced roughly as /xat/, a pronunciation that is largely preserved in the Japanese on'yomi ("Sino-Japanese") reading of the character as [katsɯ̥], as well as in Cantonese and Southern Min Chinese.

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