Source : Webster's Revised Unabridged Dictionary (1913)

Bayonet \Bay"o*net\, n. [F. bayonnette, ba["i]onnette; -- so
   called, it is said, because the first bayonets were made at
   Bayonne.]
   1. (Mil.) A pointed instrument of the dagger kind fitted on
      the muzzle of a musket or rifle, so as to give the soldier
      increased means of offense and defense.

   Note: Originally, the bayonet was made with a handle, which
         required to be fitted into the bore of the musket after
         the soldier had fired.

   2. (Mach.) A pin which plays in and out of holes made to
      receive it, and which thus serves to engage or disengage
      parts of the machinery.

   {Bayonet clutch}. See {Clutch}.

   {Bayonet joint}, a form of coupling similar to that by which
      a bayonet is fixed on the barrel of a musket. --Knight.