Note: The eyes of the Terminator I think were real but he did not rely on them, although interestingly they would have blocked his electronic eyes, so I wonder how that worked.
A robot disguised as a human is not what I meant - I mean, something that is flesh and machine, but started out purely as machine, not as a human. The robots of The Second Variety were mechanical but they also may have employed real body parts and if so, it could be argued that they preceded the idea in the Terminator except Terminators used flesh purely as camouflage. The RUR creatures are not relevant here since they are not a combination of machine and flesh but rather artificially grown flesh IIRC.
"Cyborg" to me always meant an artificially enhanced organism, but importantly, originally a naturally-born organism.
I am not sure Arnold's Terminator was a cyborg. He was a robot with real flesh added, but the skin and eyes I guess were not essential and he was, it goes without saying, never human. (In later flicks, we saw it seems to me that Skynet started out by modifying humans into cyborgs.)
So my question is, was Cameron (or whoever thought of the idea) the first to come up with a robot "enhanced" with real human tissue (although presumably the tissue was cultured, not taken from humans)?