Look of adrenaline-fuelled determination on a person's face as they engage in some kind of extreme sport. Commonly used by whitewater kayakers. The Grrr face is said to resemble one's orgasm face.
"Haha... you had the funniest grrr face going over that drop - like the river was trying to hit on your sister"
by Diarmaid June 30, 2006
by Amy February 25, 2005