a black box


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a black box

You can call a process or system a black box when you know that it produces a particular result but you do not understand how it works. What steroids do is currently something of a black box. The firm's investment success lies in its black box of formulas which identify trends. Note: In an electronic or computer system, a black box is a self-contained part. You can understand its function without knowing anything about how it works.
See also: black, box