When a snowboarder (usually a noob) catches the front edge of their stick on the snow and is instantly face-planted by the forces of inertia. Some might call this the snowboarder's version of a yardsale, which is arbitrary because in this case no gear is broken loose and sent flying down the slopes. Flyswatters are very funny to witness. Especially by skiers.
Jake: Rob, did you just see that noob flyswatter his face into the ice?
Rob: Yeah, I almost pissed my pants it was so funny!