actuator

IPA: ˈæktjueɪtɝ

Something that actuates something else.
A usually electric device that causes a mechanical device (i.e., a mechanism) to be switched on or off. For example; an electric motor that opens and closes a valve.
(computer hardware) The mechanism that moves the head assembly on a disk drive.
(electrical) A relay that controls the flow of electricity.

Examples of "actuator" in Sentences

The piston of a hydraulic actuator is coupled to the throttle.
The motor and 5: 1 gearbox are Swiss made, and the rudder actuator is sensitive to 64-steps, allowing 180-degree turns within a 12-foot-wide room.
The ribbed thing in this photo is one end of a Von Weise actuator, which is designed to tilt the dish left and right, to point at different satellites.
BGW: how about the word actuator instead of trigger with respect to Mr. Redneckerson...it carries more of the engineer chic that is so popular with the kids these days.
Ultrasonic motors (USM) are a new type actuator which is based on the concept of driving the rotor by a mechanical vibration excited on the stator via piezoelectric effect.
Applying a voltage between the indium-tin-oxide coating and the film can cause it to bend downward, into the groove in the plastic: the film becomes an "actuator" - the moving part in a MEMS.
There's an included pamphlet with a paragraph each devoted to "actuator," "worm gear" and "motor," but I understand dictionaries also contain those words, and are much more efficient at killing bugs to boot.
For example: If I'm working on the "actuator" visibility states, I don't want my valve type to change if a person wants to use a different actuator, therefore, I will select every element that is not an actuator.