1. The act of whacking off or being whacked off by a ghost or succubus.

2. The act of finding oneself whacking off a penis that has long been amputated.
Hey Melissa do you want to hit up the abandoned asylum and see if we can do some casperwhacking?

Shit I woke up casperwhacking again. I'm not sure why I still think I have a penis!? That fuckers was amputated years ago!
by SnowmanND July 5, 2018
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