linch·​pin | \ˈlinch-ˌpin \
variants: or less commonly

Definition of linchpin 

1 : a locking pin inserted crosswise (as through the end of an axle or shaft)

2 : one that serves to hold together parts or elements that exist or function as a unit the linchpin in the defense's case

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Did You Know?

There was the good old custom of taking the linch-pins out of the farmers' and bagmens' gigs at the fairs, and a cowardly blackguard custom it was. That custom, described by British writer Thomas Hughes in his 1857 novel Tom Brown's School Days, was "blackguard" indeed. The linchpin in question held the wheel on the carriage and removing it made it likely that the wheel would come off as the vehicle moved. Such a pin was called a "lynis" in Old English; Middle English speakers added "pin" to form "lynspin." Modern English speakers modified it to "linchpin" and, in the mid-20th century, began using the term figuratively for anything as critical to a complex situation as a linchpin is to a wagon.

Examples of linchpin in a Sentence

This witness is the linchpin of the defense's case.

Recent Examples on the Web

The handwritten accounting document, called in Ukraine the Black Ledger, is an evidential linchpin for investigating corruption in the former government. New York Times, "Ukraine, Seeking U.S. Missiles, Halted Cooperation With Mueller Investigation," 2 May 2018 Adrien Rabiot is thought to be closing in on a move from PSG after reportedly agreeing personal terms, but Kante could be the defensive midfield linchpin that makes the whole team click., "Barcelona Join Race for Chelsea Midfielder N'Golo Kante With Cash Plus Player Deal," 13 July 2018 Harland Sanders' secret original recipe for his famed fried chicken, the linchpin of KFC's global franchise of some 18,000 restaurants in 115 countries. Kathryn Gregory, The Courier-Journal, "Is this KFC's secret original recipe for its famed fried chicken?," 6 July 2018 There’s also a floor map outlining the Ohio, Missouri and Mississippi rivers and St. Louis’ geographic and historic linchpin to the waterways that open the west. Gary Garth, USA TODAY, "Gateway Arch: An American classic gets a major overhaul," 29 June 2018 To a first-time visitor, the village does not look like the contested linchpin of two dueling national destinies. New York Times, "As Israel Pushes to Build, Bedouin Homes and School Face Demolition," 24 June 2018 Then there's the 1970s case where police monitored an obscene phone caller, which led to the legal decision that formed the linchpin of the NSA's controversial metadata tracking program revealed by Edward Snowden. Annalee Newitz, Ars Technica, "Bay Area: Join us 6/13 to discuss the past, present, and future of tech law," 11 June 2018 These same support networks could serve as the linchpin of successful disengagement and reintegration. Julie Chernov Hwang, Washington Post, "New research shows why terrorists quit terrorism," 12 July 2018 Alice must be a credible linchpin between two improbable halves of narrative, and Cardwell is. Lawrence Toppman, charlotteobserver, "‘Bright Star,’ a musical tale of NC mountain life, glows steadily and endearingly," 27 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'linchpin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of linchpin

13th century, in the meaning defined at sense 1

History and Etymology for linchpin

Middle English lynspin, from lyns linchpin (from Old English lynis) + pin; akin to Middle High German luns linchpin

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Statistics for linchpin

Last Updated

12 Nov 2018

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Time Traveler for linchpin

The first known use of linchpin was in the 13th century

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More Definitions for linchpin



English Language Learners Definition of linchpin

: a person or thing that holds something together : the most important part of a complex situation or system

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playful or foolish behavior

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