A rash/burn developed at frat parties when a person is jammed between a wall and someone else's ass and the friction between the wall and himself causes a rash/burn.
"Dude, it was so packed in there and that girl with the huge badonkadonk was grindin' so hard up against me, I think I got fratburn."
by Jericho Piebald March 12, 2012
Get the fratburnmug.