bionics

the word bionic was coined by Jack E. Steele in 1958, possibly originating from the technical term bion (pronounced bee-on) (from Ancient Greek: βίος), meaning 'unit of life' and the suffix -ic, meaning 'like' or 'in the manner of', hence 'like life'
Some dictionaries, however, explain the word as being formed as a portmanteau from biology + electronics.
Bionics, the study of the functions of living organisms for the purpose of building mechanical or electronic devices to copy or imitate these functions. Much of the work done in bionics has been experimental, but bionics has led to a number of practical medical and industrial devices. Medical devices developed through bionics include kidney-dialysis machines and computer-controlled artificial limbs. ( Artificial Limb; Kidney, subtitle Kidney Disorders: Kidney Failure.) Industrial devices developed through bionics include robots used to perform repetitive tasks, such as assembling automobile parts. Much research in bionics concerns the development of computers that can perform functions ordinarily associated with human intelligence.

In medicine

Bionics is a term which refers to the flow of concepts from biology to engineering and vice versa. Hence, there are two slightly different points of view regarding the meaning of the word.
In medicine, bionics means the replacement or enhancement of organs or other body parts by mechanical versions. Bionic implants differ from mere prostheses by mimicking the original function very closely, or even surpassing it.
Bionics' German equivalent, Bionik, always adheres to the broader meaning, in that it tries to develop engineering solutions from biological models. This approach is motivated by the fact that biological solutions will usually be optimized by evolutionary forces.