galvanometer /gal′vənom″ətər/ [Luigi Galvani] , an instrument used to measure the strength and direction of flow of an electric current. Its action depends on the deflection of a magnetic needle in the field produced by current passing through a coil. A simple galvanometer is used mainly to detect the presence of an electric current. Galvanometers are used in certain diagnostic instruments, such as electrocardiographs.
