Merriam-Webster's Collegiate® Dictionary, 11th Edition
GIBBET
I. noun
Etymology: Middle English gibet, from Anglo-French
Date: 13th century
gallows 1a, an upright post with a projecting arm for hanging the bodies of executed criminals as a warning,
II. transitive verb
Date: 1646
1. to expose to infamy or public scorn, to hang on a gibbet, to execute by hanging on a gibbet