CHOCK (3)

Chock, n. 1. 1. A wedge, or block made to fit in any space which it is desired to fill, esp. something to steady a cask or other body, or prevent it from moving, by fitting into the space around or beneath it.
2. 2. (Naut.) A heavy casting of metal, usually fixed near the gunwale. It has two short horn-shaped arms curving inward, between which ropes or hawsers may pass for towing, mooring, etc.