'Swivel bridge' definitions:

Definition of 'Swivel bridge'

From: GCIDE

Swivel \Swiv"el\, n. [AS. sw[imac]fan to move quickly, to remove; akin to Icel. sveifla to whirl, shake, sv[imac]fa to ramble, to turn. See Swoop, and cf. Swift a reel, Swift, a.]
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. [1913 Webster]
2. (Mil.) A small piece of ordnance, turning on a point or swivel; -- called also swivel gun. --Wilhelm. [1913 Webster]
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. [1913 Webster]