A weapon which throws or propels a missile to a distance; any
   firearm or instrument for throwing projectiles by the explosion of
   gunpowder, consisting of a tube or barrel closed at one end, in which
   the projectile is placed, with an explosive charge behind, which is
   ignited by various means. Muskets, rifles, carbines, and fowling pieces
   are smaller guns, for hand use, and are called small arms. Larger guns
   are called cannon, ordnance, fieldpieces, carronades, howitzers, etc.
   See these terms in the Vocabulary.