A term used to describe the colliding of two objects, or the forceful movement of one object, such as the head or a limb.
Sarah was driving in her car with Katrina, and they were looking out the sunroof at the night sky. They wanted to see the moon, so Sarah put the car in reverse and stepped on the gas. At 40 miles an hour, a light pole jumped out of no where and Sarah hit it, and her head was like, "wampa chanka."
by Jac the Pip July 17, 2006