Kiai

Kiai(気合) /ˈkiː.aɪ/ is a Japanese term used in martial arts for the short yell or shout uttered when performing an attacking move.

Traditional Japanese Dojo generally use single syllables beginning with a vowel. The concept has become a notable part of Asian martial arts in popular culture, especially in martial arts films, in writing rendered in variants such as Hi-yah!, Aiyah!, Eeee-yah!, or Hyah!.