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

The plane's black box was found on farmland near the crash site.

From Barron's

“It’s a black box in the beginning with the construction-in-progress bucket and then once the project is complete, it’s a black box in the back end,” Carnes said.

From The Wall Street Journal

Turkish authorities found the cockpit voice recorder and black box from a private jet that crashed Wednesday killing the head of Libya's armed forces and his four aides.

From Barron's

The Grand is the furthest thing from a corporate, black box, chain theater that one could conceive.

From Salon

They wanted to rewrite the playbook and bring that type of comedy out of 75-seat black boxes behind coffee shops.

From Los Angeles Times