1 definition by Gary K.

A Butt Worm (or pinworm) is a parasite often found in feces, and the eggs can be spread about very easily upon contact. Having Butt Worms often leads to itchy/crawly sensations
It's a good thing I don't work in the stables, I don't wanna get any butt worms.
by Gary K. June 12, 2008
Get the butt worm mug.