This is when you kick a woman in the vagina, and your foot gets stuck and when you pull your foot out the force is such that you shred the vagina.
Emergency Room: "Is she in labour?"
"No, it's just a rugged shark."
The practice of urinating on your school dean, without them knowing.
Your school dean comes up to you and your mates and starts to tell you off. So one of you moves behind him and starts to urinate on the back of his leg. The noise made is like a patter, hence the name.