Definitions of cannon:

noun: lower part of the leg extending from the hock to the fetlock in hoofed mammals
noun: a large artillery gun that is usually on wheels
noun: heavy automatic gun fired from an airplane
noun: (Middle Ages) a cylindrical piece of armor plate to protect the arm
noun: heavy gun fired from a tank
noun: a shot in billiards in which the cue ball contacts one object ball and then the other
verb: fire a cannon
verb: make a cannon
name: A surname (common: 1 in 3333 families; popularity rank in the U.S.: #373)