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

See Examples For:

black box

For many people, dealing with an insurance company can feel like navigating a black box of restrictions and jargon.

From MarketWatch ● Aug. 13, 2026

It was photographed in a large square black box on a wooden desk.

From BBC ● Jun. 23, 2026

"It's like looking at a black box," LaSala added.

From Science Daily ● Jun. 2, 2026

It took almost two years and multiple search campaigns to find the wreckage and the plane’s black box recorders.

From The Wall Street Journal ● May 21, 2026

It seemed impossible that he could be inside that long black box that was lying in the middle of the courtyard.

From "The House of the Spirits: A Novel" by Isabel Allende