black box

American  

noun

1. any unit that forms part of an electronic circuit and that has its function, but not its components, specified.

2. any comparatively small, usually black, box containing a secret, mysterious, or complex mechanical or electronic device.

3. Aeronautics. an electronic device, such as a flight recorder, that can be removed from an aircraft as a single package.

4. Automotive. a device in an electronic ignition system that generates electrical pulses.

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black box British  

noun

1. a self-contained unit in an electronic or computer system whose circuitry need not be known to understand its function

2. an informal name for flight recorder

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black box Cultural  

1. A crash-resistant steel container that holds instruments that record performance data in airplanes. The data are used to analyze the causes of accidents.

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Etymology

Origin of black box

First recorded in 1940–45

Example Sentences

Many simulations simplify chips as "black boxes" because of computational limits, but access to thousands of GPUs allowed the researchers to model the actual physical structure and behavior of the device.

From Science Daily

“The concerns are because it’s such a black box,” said Bobby Reddy, a professor of corporate law and governance at the University of Cambridge.

From The Wall Street Journal

Imagine opening a black box, only to find 5,000 more black boxes inside.

From The Wall Street Journal

“Venezuela was a black box. It is a territory in which we have blinded ourselves,” says Fulton Armstrong, a former CIA analyst.

From The Wall Street Journal

Despite multiple searches, including the largest in aviation history, neither the aircraft, passengers nor black boxes have ever been found.

From Barron's