'Servo-motor' definitions:

Definition of 'Servo-motor'

From: GCIDE

Servo-motor \Ser`vo-mo"tor\ (s[~e]r`v[-o]*m[=o]"t[~e]r), n. [Sometimes erroneously spelt serro-motor.] [F. servo-moteur. See Serf; Motor.]
1. (Mach.) A relay apparatus; specif.: (a) 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) In a Whitehead torpedo, a compressed-air motor, for moving the rudders so as to correct deviations from the course. [Webster 1913 Suppl.]
2. a motor which forms part of a servomechanism. [PJC]