Prolonged leaning forward on the elbows whilst engaging in iPhone gaming during the act of having a particularly tricky bowel movement. With the result of leaving a prominent red mark on the thigh saluting your efforts.
After a heavy drinking session on the Guinness, I was birthing a beast from my ass whilst trying to beat that tricky level on Angry Birds and it left me with serious Shitters Knee.
by DeNinjabreadman December 26, 2011
The red marks that show up on your knees when a lot of time has been reading, texting, or using a smartphone on the toilet.
Steve: "Did you have a good shit?"
Jamie: "Dang right I did."
Steve: "Yeah I can see your shitter's knee with those shorts on."
Jamie: "Dang right I did."
Steve: "Yeah I can see your shitter's knee with those shorts on."
by Magikchef01 October 15, 2013