1. Tennis.the point that if won would enable the scorer or his or her side to win the set.
Pronunciation: (set'point"), [key]
1. the desired value in a closed-loop feedback system, as in regulation of temperature or pressure.
2. the point at which a thermostat has been set, as for optimum efficiency.
3. Physiol.an internal regulatory system for maintaining a relatively stable physiological condition in the face of changing external circumstances, as body temperature in a varying climate. Cf. homeostasis.
4. a hypothetical regulator in the body that maintains a relatively stable body weight.
5. the weight range thus theoretically maintained. Also,set point.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.