—n. 1. a ring or other fastening, as of iron, for securing the wrist, ankle, etc.; fetter.
2. a hobble or fetter for a horse or other animal.
3. the U-shaped bar of a padlock, one end of which is pivoted or sliding, the other end of which can be released, as for passing through a staple, and then fastened, as for securing a hasp.
4. any of various fastening or coupling devices.
5. Often, shackles. anything that serves to prevent freedom of procedure, thought, etc.
—v.t. 1. to put a shackle or shackles on; confine or restrain by a shackle or shackles.
2. to fasten or couple with a shackle.
3. to restrain in action, thought, etc., as by restrictions; restrict the freedom of.