1.(Railroad) A turning off to a side or short track, that the principal track may be left free.
2.(Elec.) A conducting circuit joining two points in a conductor, or the terminals of a galvanometer or dynamo, so as to form a parallel or derived circuit through which a portion of the current may pass, for the purpose of regulating the amount passing in the main circuit.
3.(Gunnery) The shifting of the studs on a projectile from the deep to the shallow sides of the grooves in its discharge from a shunt gun.
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