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

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

From Science Daily ● Jun. 2, 2026

“It’s a black box to us,” says Foundation of Hearts chairman Gerry Mallon.

From The Wall Street Journal ● May 15, 2026

Motability drivers will no longer need to have a black box fitted to their vehicles following criticism from users affected by the rule changes.

From BBC ● May 14, 2026

Nearby, a new black box theater with high curved ceilings and 200 seats is meant to have a soft look.

From Los Angeles Times ● May 4, 2026

Opens it and pulls out a black box.

From "Dear Martin" by Nic Stone