lesbian jaw
A chiseled, square, jaw-structure on a woman. This is often known to lead to the rejection of cock and and the diving of muffs. The squareness of the jaw is thought to have evolved naturally to aid in long sessions resting on a female taint.
Dude, I don't care how hot you think Lisa is, she's got mad lesbian jaw. You better hit that before she goes to college while you still can.