The Cannon is a underused art in most professional sport, however it is slowly being reintroduced by purists of the game, it is now most commonly found in hockey at it highest level. Hockey allows the ball to be hit in a constantly rising trajectory until it is stopped only by the net.
When someone is dissed so bad to the point that to make them feel better is by humiliating them even more. This term is an NYC term to draw attention to the victim and in fact making the victim feel even worst than before. You must also yell the word cannon otherwise it won't be used in the correct sense.
Person B: Maybe she got better dick than you son
Person C: CANNON!!