Servo-motor
Servo-motor (sẽr`vo*mō"tẽr) , noun
[Sometimes erroneously spelt serro-motor.]
1.
(Machinery) A relay apparatus;
(a)
(Machinery) An auxiliary motor, regulated by a hand lever, for quickly and easily moving the reversing gear of a large marine engine into any desired position indicated by that of the hand lever, which controls the valve of the motor.
(b)
(Machinery) In a Whitehead torpedo, a compressed-air motor, for moving the rudders so as to correct deviations from the course.
2.
a motor which forms part of a servomechanism.