3 ms·Canon is a short Cannon, for close quarters shelling or installation on narrow ships.by a3n 9y agoCanon is a short Cannon, for close quarters shelling or installation on narrow ships.TeMPOraL 9y agoThis is my headcanon now. Do not confuse with a head cannon.mcguire 9y agoIs a head cannon a device for projecting noggins or an article of millinery?