Fetterlock

Part of speech: noun

Definitions

1. A type of padlock with a U-shaped shackle used to clasp chains around a prisoner's ankles ; a figure in heraldry showing this kind of open shackled lock
2. A padlock whose curved shackle is designed to secure leg irons or fetters ; a symbol in coats of arms representing that shackle lock
3. A lock with an arched bar meant to fasten fetters on a captive's legs ; an emblem drawn on a coat of arms in the form of that lock

Etymology: A fetterlock is a lock that hangs from a shackle or chain, or a metal fastening used on a horse's leg to keep it from straying. The word is a plain compound: "fetter," the chain or shackle placed on a prisoner's or animal's ankles, joined to "lock," the mechanism that secures it. Both halves are old English words, so the word needs no foreign detour to explain it. The pairing makes sense once you picture the object. A fetter restrains movement by binding the feet, and a fetterlock is the device that closes such a binding, so the compound names the fastening itself rather than the restraint in general. Its meaning has stayed close to that literal sense, which is part of why the word reads so transparently today.

Synonyms: shackle, fetter