The act of taking a shit so hard that it sticks to the toilet bowl similar to the way semtex sticks to surfaces/people in the Call Of Duty series.

Sometimes it even has the ability to withstand the force of a flush or two.
Person 1: "Yo man, I just took one hell of a shit, it's stuck on like semtex and it won't flush away, what should I do?"

Person 2: "Oh you took a semtex shit? Its cool, just leave it for the cleaner, I'm sure she won't mind."

*Later that day....*

Cleaner: "WHYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY?!?!"
by wisemen experience May 22, 2011
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