Galvanometer

Part of speech: noun (n.)

An instrument or apparatus for measuring the intensity of an electric current, usually by the deflection of a magnetic needle. Differential galvanometer. See under Differental, a. -- Sine galvanometer, Cosine galvanometer, Tangent galvanometer (Elec.), a galvanometer in which the sine, cosine, or tangent respectively, of the angle through which the needle is deflected, is proportional to the strength of the current passed through the instrument.