How can we use it? We find out what it means from a dictionary (or preferably 2 or 3), for example the one below, then we use it consistently with the definition.
For example, "My father had a bionic hand fitted after he lost his own in a tractor accident."
Adjective:1. Having artificial body parts, esp. electromechanical ones.
2. Having ordinary human powers increased by or as if by the aid of such devices (real or fictional).
More info »Dictionary.com - Answers.com - Merriam-Webster - The Free Dictionary
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