Entry from OED Online

[Blend of CYB(ERNETIC a. and ORG(ANISM.] 

    A person whose physical tolerances or capabilities are extended beyond normal human limitations by a machine or other external agency that modifies the body's functioning; an integrated man-machine system.
 
  1960 N.Y. Times 22 May 31/1 A cyborg is essentially a man-machine system in which the control mechanisms of the human portion are modified externally by drugs or regulatory devices so that the being can live in an environment different from the normal one. 1960 CLYNES & KLINE in Astronautics Sept. 27/1 For the exogenously extended organizational complex functioning as an integrated homeostatic system unconsciously, we propose the term ‘Cyborg’. The Cyborg deliberately incorporates exogenous components extending the self-regulatory control function of the organism in order to adapt it to new environments. 1966 C. M. CADE Other Worlds than Ours x. 218 The ‘Cyborg’—which is the name..for animal-machine combinations—seems to be the man of the future. 1970 A. TOFFLER Future Shock ix. 185 Advanced fusions of man and machine—called ‘Cyborgs’—are closer than most people suspect. 1976 Physics Bull. June 266/1 There is a fundamental limit to the mass for a given rate of information processing... Perhaps even the most advanced cyborgs stop far short of this theoretical limit. 1984 M. AMIS Money 308, I am a robot, I am an android, I am a cyborg, I am a skinjob.