(humorous, often) Accompanying an attacking move in (parodies of) Eastern martial arts such as karate.
I double over and hear a karate ninja sound. “Hi Yah!” A sharp chop to my neck brings me down to the floor. What just happened? 2020, K. Anthony Wilson, Better Together:
She leaped down beside him and took a karate stance. “Hi-yah!” she shouted. She kicked as high as she could, first with one foot, then with the other. 2017, Jerry Mahoney, My Rotten Stepbrother Ruined Snow White, page 101: