Is there a human in the room?

Yesterday a friend challenged me on my characterization of the Terminator as a cyborg, pointing out that he does not in fact possess any critical organic components, and that therefore I should have referred to him as an android. This is of course correct, a cyborg, as the OED tells us, being 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."

It galls me to be accused of sloppy use of the English language, so I've been thinking about the implications of the word cyborg (cyb[er] org[ansim]). Cybernetics is the study of communications systems in biological, social, and, of course, IT contexts. It involves the existence of feed back loops, ie systems able to respond to stimuli. The nervous system is a good example of this; it operates by collecting external and internal data which it then uses to determine how to interact with its environment. So we organisms are all cybernetic, and the lines become even more difficult to draw when you consider that an organic body is only a tool or machine developed by DNA.

Of course, this doesn't help me with the Terminator, who, being metal, falls short in the -org department. Nevertheless, I'm left wondering: if my organic body is a machine like the Terminator's metal body is, and if we both operate using cybernetic systems, does our difference depend only upon the materials of which we are composed? All right, he's a bit more muscular than me too - but is that all?