Overjaw

And when they eat, they move the overjaw and nought the nether jaw, and they have no tongue.

The King was now represented with a receding forehead, a lined and haggard face, a long nose, thick lips, slanting eyes, a hanging overjaw, and hollow cheeks.

He drove her over the Hayward Fault, its boundaries jammed together like an overjaw clenched to an underjaw.