°A restraint fit over a human or animal appendage, such as a wrist, ankle or finger. Usually used in plural, to indicate a pair joined by a chain.
°A U-shaped piece of metal secured with a pin or bolt across the opening, or a hinged metal loop secured with a quick-release locking pin mechanism. Sometimes referred to as a D shackle, a D closure or a green pin shackle.
verb
°To restrain using shackles; to place in shackles.