Sticking ones finger in the anus of another while they walk up the stairs. Usually accompanied by a wiggling motion and shouting "Butt Worm!"
by Capt. Josh January 04, 2011
by Allen Schmidt May 09, 2003
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
by Gary K. June 12, 2008
Mexican butt-worms are what you pick up in mexico after eating from a taco cart or tamale stand that is less than sanitary. They are also different from other butt-worms because they wear sombreros.
Did you hear about Steve's trip to Tijuana? He got a bad case of the mexican butt-worms after eating at a filthy taco stand.
by Weslitzu December 30, 2013
When you see something that scares or disgusts you so much... that you clinch your buttcheeks so tightly, that not even a worm could get inside.
by Brownie ESQ July 08, 2010