black box

1 of 2

noun

1

: a usually complicated electronic device whose internal mechanism is usually hidden from or mysterious to the user

broadly : anything that has mysterious or unknown internal functions or mechanisms

2

: a crashworthy device in aircraft for recording cockpit conversations and flight data

3

: a device in an automobile that records information (such as speed, temperature, or gasoline efficiency) which can be used to monitor vehicle performance or determine a cause in the event of an accident

black box

2 of 2

adjective

: being or containing a warning of a serious or life-threatening side effect (such as stroke or muscle damage) that is highlighted by a black border on a prescription drug's label or accompanying literature

Examples of black box in a Sentence

Noun

The black boxes were recovered from the crash site and provided useful information about the cause of the crash.

Recent Examples on the Web

Noun

Bradley Taylor, who lives within walking distance, figured the small black box of a building would be an affordable place to launch The Donut Trap, an homage to his favorite Los Angeles doughnut shop and his love of the arts. —Frederick Melo, Twin Cities, 11 Sep. 2025

The leaders who thrive will be those who treat AI agents not as magical black boxes, but as capable yet fallible teammates: giving them clear objectives, the right roles, structured onboarding, iterative coaching, and informed trust. —Nick Lichtenberg, Fortune, 5 Sep. 2025

Adjective

Two antipsychotic drugs are approved to treat irritability associated with ASD, but both come with a black box warning about safety, and neither addresses the underlying medical issues presented with autism, according to Ackerman. —Amanda Musa, CNN Money, 24 Sep. 2025

The Arvada Police Department arrested a 41-year-old man in connection with the discovery of a 29-year-old woman’s body inside of a black box next to a dumpster near an apartment building. —Elizabeth Hernandez, Denver Post, 19 Sep. 2025

Word History

First Known Use

Noun

circa 1945, in the meaning defined at sense 1

Adjective

1968, in the meaning defined above

Rhymes for black box

• botox
• checkbox
• comox
• cornstalks
• cowpox
• crosswalks
• deadlocks
• detox
• feedstocks
• firebox
• gearbox
• hemlocks

Medical Definition

black box

adjective

: being or containing a warning of a serious or life-threatening side effect (as stroke, muscle damage, or suicidal tendencies) that is highlighted by a black border on a prescription drug's label or accompanying literature

A "black box" warning is the most serious warning placed in the labeling of a prescription medication.

—Johnathan D. Rockoff, The Fort Worth (Texas) Star-Telegram