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?!?!"