<p><strong>Noun, plural cannons</strong></p><ul><li>a mounted gun for firing heavy projectiles; a gun, howitzer, or mortar</li><li>British Machinery: quill (def 10)</li><li>Armor: a cylindrical or semicylindrical piece of plate armor for the upper arm or forearm; a vambrace or rerebrace</li><li>Also called cannon bit: a round bit for a horse</li><li>the part of a bit that is in the horse's mouth</li><li>(on a bell) the metal loop by which a bell is hung</li><li>Zoology: cannon bone</li><li>the part of the leg in which the cannon bone is situated</li><li>British: a carom in billiards</li><li>Underworld Slang: a pickpocket</li></ul><p><strong>Verb (used without object)</strong></p><ul><li>to discharge cannon</li><li>British: to make a carom in billiards</li></ul>