- the study of how humans and animals perform certain tasks and solve certain problems, and of the application of the findings to the design of electronic devices and mechanical parts.
- the study of certain biological functions, esp those relating to the brain, that are applicable to the development of electronic equipment, such as computer hardware, designed to operate in a similar manner
- the technique of replacing a limb or body part by an artificial limb or part that is electronically or mechanically powered
