When someone yanks upward on your underwear. Usually done on weaker people or done in a group to average/stronger people. It induces a large amount of pain towards the crotch/ass. Incredibly painful and there are a large variety of techniques. Hurts more if the reciever of the wedgie is wearing tighty whities (briefs). As tidey whities tend to take longer to rip(escpecially Fruit of the Loom and Hanes), and they stretch farther. They're also harder to un-wedge, and go deeper into your crack. Opposed to boxers, which rip easier, easier to un-wedge, and don't irritate and hurt as much.
Boxer wearer's tend to pick on a tighty wighty wearer through the wedgie. The wedgie is also a common locker room use. Should someone be shown to wear tidey whighties (briefs) then they should be the victim of many wedgies into the future and beyond until everyone seems fit.
"I wear tighty whities and while changing in the locker room, a student saw me and screamed out TIGHTY WHITIES! While I tried my best to change, a rather large guy, grabbed the waist band and yanked up incredibly hard. I was immobilized and 4 other guys came and yanked upwards as well. My lower area was burning incredibly and I couldn't stop it. ALl 4 of them spit into my underwear as they yanked, giving me a messy wedgie and causing much pain and irritation. They finally stopped and took my stuff leaving me in nothing but my thong-ed out briefs. Ever since then, I have been the victim of many unfortunate wedgies."