swivel(3. a. a pivot on which is mounted a gun that may be swung from side to side in a horizontal plane
b. Also called: swivel gun – the gun itself
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swivel gun(The term swivel gun (or simply swivel) usually refers to a small cannon, mounted on a swiveling stand or fork which allows a very wide arc of movement. Another type of firearm referred to as a swivel gun was an early flintlock combination gun with two barrels that rotated along their axes to allow the shooter to switch between rifled and smoothbore barrels. Swivel guns should not be confused with pivot guns, which were far larger weapons mounted on a horizontal pivot, or screw guns, which are a mountain gun with a segmented barrel. wikipedia.org)
