Swiv·el n.
 1. Mech. A piece, as a ring or hook, attached to another piece by a pin, in such a manner as to permit rotation about the pin as an axis.
 2. Mil. A small piece of ordnance, turning on a point or swivel; -- called also swivel gun.
 Swivel bridge, a kind of drawbridge that turns round on a vertical axis; a swing bridge.
 Swivel hook, a hook connected with the iron strap of a pulley block by a swivel joint, for readily taking the turns out of a tackle.
 Swivel joint, a joint, the two pieces composing which turn round, with respect to each other, on a longitudinal pin or axis, as in a chain, to prevent twisting.