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

When you gaze into the black box, the black box calculates how best to gaze back.

From Slate ● Sep. 18, 2026

Fashion heist films watched in a black box theater.

From Los Angeles Times ● Sep. 16, 2026

Recovering the vessel's "black box" would help understand what caused the tragedy, he added.

From Barron's ● Aug. 31, 2026

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

From BBC ● Jun. 23, 2026

He reaches toward the coffee table separating us and picks up a small black box resting on top of a stack of game magazines.

From "Warcross" by Marie Lu