A circuit usually diagrammed as a square formation of components that gives a null indication on a sensing device when a balance is achieved.
A type of circuit intended to "bridge" or "bypass" another circuit, causing a "null" or no current to be measured.
A bridge circuit is a type of electrical circuit in which the current in a conductor splits into two parallel paths and then recombines into a single conductor, thereby enclosing a loop. It was originally used for measurement purposes, but can also be used in power supplies.