Definition of controller :
1. A kind of multiple switch for gradually admitting the current to, or shutting it off from, an electric motor; as, a car controller for an electric railway car.
2. A lever controlling the speed of an engine; - applied esp. to the lever governing a throttle valve, as of a steam or gasoline engine, esp. on an automobile.
3. An electromagnet, excited by the main current, for throwing a regulator magnet into or out of circuit in an automatic device for constant current regulation.
4. Any electric device for controlling a circuit or system;
treasurer (part of speech: noun)
- The lad nodded grimly, and shoved the controller handle over to the last notch. - "Tom Swift and his Electric Runabout or, The Speediest Car on the Road", Victor Appleton.
- Amidst these infernal surroundings the ruler of Hades Uplifted his head by the funeral flames silhouetted And sprinkled with white from the ashes of corpses; and challenged Winged Fortune in words such as these: 'Oh thou fickle controller Of things upon earth and in heaven, security's foeman, Oh Chance! - "The Satyricon, Complete", Petronius Arbiter.
- But why would a Controller do it? - "The Penal Cluster", Ivar Jorgensen (AKA Randall Garrett).