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jack in

British  

verb

  1. slang (tr, adverb) to abandon or leave (an attempt or enterprise)

"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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Farron's flag also featured a union jack in one corner.

From BBC • Sep. 20, 2025

“Magazines; more records; books; memorabilia; programs; CDs; VHS; stacking dolls. There’s a jack in the box with a Barbra inside; a Fabergé-style egg.”

From Los Angeles Times • Dec. 18, 2023

It’s typically connected to a cable jack in your wall.

From Washington Post • Mar. 3, 2023

Time to jack in and figure it out.

From The Verge • Oct. 4, 2021

I have a hard time looking jack in the eye, even though we’re friends now.

From "The House That Lou Built" by Mae Respicio

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.