football injury
Used to describe a woman with a very wide posterior; used to describe a woman who looks as if a football was punted sideways into her ass
*woman walks by* "Oh, would you look at the football injury on that..."
old football injury
An injury caused by excessive masturbation in a man over the age of 30.
Girl: Aw, what happened? Why is your arm in that sling?
Guy: It's an old football injury.
Guy: It's an old football injury.