The invention relates to an actuator 1 comprising a housing 8, a coil 29 and an armature 2 which interacts with a tappet 30 and a spring, the armature plate 3 thereof being arranged to lie opposite an armature counterpiece 16, and said actuator 1 comprising at least one magnetostrictively-active component. According to the invention, an actuator 1 is provided with which large actuating paths can be travelled at high actuating forces. This is achieved by the actuator 1 additionally being designed to act as a solenoid.