Dictionary.net

A large stone reaching through a wall so as to appear on both sides of it, and acting as a binder; - called also perbend, perpend stone, and perpent stone.

A large stone reaching through a wall so as to appear on both sides of it, and acting as a binder; - called also perbend, perpend stone, and perpent stone.

n. [French] A large stone reaching through a wall on both sides, and wrought at the ends; ashlar stone.