What does "cannon" mean?

Cannon: (Mech.) A hollow cylindrical piece carried by a revolving shaft, on which it may, however, revolve independently.

Additional senses

  1. 2.(Printing.) A kind of type. See Canon. Cannon ball, strictly, a round solid missile of stone or iron made to be fired from a cannon, but now often applied to a missile of any shape, whether solid or hollow, made for cannon. Elongated and cylindrical missiles are sometimes called bolts; hollow ones charged with explosives are properly called shells. -- Cannon bullet, a cannon ball. [Obs.] -- Cannon cracker, a fire cracker of large size. -- Cannon lock, a device for firing a cannon by a percussion primer. -- Cannon metal. See Gun Metal. -- Cannon pinion, the pinion on the minute hand arbor of a watch or clock, which drives the hand but permits it to be moved in setting. -- Cannon proof, impenetrable by cannon balls. -- Cannon shot. (a) A cannon ball. (b) The range of a cannon.
  2. 3.See Carom. [Eng.]

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