jack-in-the-box

American  

[jak-in-thuh-boks] / ˈdʒæk ɪn ðəˌbɒks /

Or jack-in-a-box

noun

plural

jack-in-the-boxes

1. a toy consisting of a box from which an enclosed figure springs up when the lid is opened.

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jack-in-the-box British  

noun

1. a toy consisting of a figure on a compressed spring in a box, which springs out when the lid is opened

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Etymology

Origin of jack-in-the-box

First recorded in 1545–55

Explanation

Do you enjoy being startled? Try playing with a jack-n-the-box. Operated with a crank, this kind of music box plays a little tune until a clown suddenly pops out of an opening in the top. Fun! A jack-in-the-box can be a bit terrifying, especially to a very small child who's not expecting to see a scary (or smiling) face emerge abruptly from a colorful music box. The history of this strange toy emphasizes its frightening nature. In France, it's called diable en boîte, or "devil in a box," and is thought to be inspired by a 14th-century English folklore hero who captured the devil in his boot.

Example Sentences

"As far as anyone knew, the T cell receptor didn't undergo any conformational changes when binding to these antigens. But we found that it does, springing open like a sort of jack-in-the-box."

From Science Daily • Dec. 18, 2025

Pakistan's jack-in-the-box surprise element now feels akin to a cliche from a bygone era.

From BBC • Feb. 23, 2025

While not wildly original, his jack-in-the-box surprises are skillfully, tautly executed.

From New York Times • Oct. 20, 2022

Her mother is a "rag doll of a woman" and her dad a "jack-in-the-box," while a refrigerator is a "giant potato."

From Salon • Jul. 19, 2021

Richard Parker could shred it with his claws with a little time and effort, but he couldn’t pop through it like a jack-in-the-box.

From "Life of Pi" by Yann Martel