in which the h-sound is produced in the back of the throat and the 'a' is silent, is the sound one makes to emphasize how empty an action, reaction or situation is.
The sound one makes while pretending to hit someone. Usually it is accompanied by a karate style hitting motion. If this vocalization and action is performed by oneself and you are unknowingly observed by a friend or coworker, you will be laughed at and subsequently humiliated. The evolution of HI-YAH!
Tricia surprised me in the gift shop when I was WHA-PSHHH ing. I went WHA-PSHHHH and she still hasn’t stopped laughing