( noun ) The Twizm or Twizm's are the flaps of skin in front of and behind the Rectum. It is there to Ensure that fecies do not leave the region of your anal cavity. When you wipe from front to back or vise versa, you do not get shit on your balls or vagina, and same for your lower back.
I'm glad i have a twizm so i don't get shit on my balls.
by Soldier in the shit December 10, 2005
Happy St. Patties Day!