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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.

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of jack-in-the-box

First recorded in 1545–55

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.