The Collaborative International Dictionary of English v.0.48:
Bayonet \Bay"o*net\, n. [F. bayonnette, ba["i]onnette; -- so
called, it is said, because the first bayonets were made at
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.
bayonet mount, (photography) a coupling mechanism for
attaching removable lenses to the body of a camera, using
a bayonet socket.
bayonet socket, a coupling mechanism for attaching matching
cylindrical parts to each other, where each of which has
an arced L-shaped slot with the longer side perpendicular
to the axis of the cylinder, such that the slots slide
inside each other. There is also usually a knoblike
projection on the mount so that when the two parts to be
connected are fully inserted in proper alignment, they are
locked in place. It is designed for rapid coupling and
decoupling, requiring the turning of one part through only
a small arc, in place of a screw-type arrangement, which
requires several full turns.
[1913 Webster +PJC]