Definition of: governor

(guv′ər·nər) noun
1. One who governs; especially, the chief executive of a state or colony.
2. Mech. A device for regulating the speed of an engine, motor, compressor, etc., usually by the centrifugal force of two or more balls or weights, which so control the motive fluid as to reduce speed: also called ball–governor.
3. Brit. Colloq. One's father.
4. Brit. Colloq. An employer. See synonyms under MASTER.
BALL–GOVERNOR
The balls, revolving, raise levers to position A, thus reducing excess speed of engine by closing valve at B.