(1):

(n.) A device, as a bar, for operating two brakes, esp. a pair of hub brakes for an automobile, with equal force.

(2):

(n.) One who, or that which, equalizes anything.

(3):

(n.) Any device for equalizing the pull of electromagnets; also, a conductor of low resistance joining the armature ends of the series field coils of dynamos connected in parallel.

(4):

(n.) = Equalizing bar.

(5):

(n.) A sliding panel to preserve the lateral stability of an aeroplane.