linchpin

American  

[linch-pin] / ˈlɪntʃˌpɪn /

Or lynchpin

noun

1. a pin inserted through the end of an axletree to keep the wheel on.

2. something that holds the various elements of a complicated structure together.

   The monarchy was the linchpin of the nation's traditions and society.

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linchpin British  

/ ˈlɪntʃˌpɪn /

noun

1. a pin placed transversely through an axle to keep a wheel in position

2. a person or thing regarded as an essential or coordinating element

   the linchpin of the company

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Usage

What does linchpin mean? A linchpin is the person or thing that serves as the essential element in a complicated or delicate system or structure—the one that holds everything together. This sense of linchpin is based on its original, literal meaning: an actual pin used to attach a wheel to the axle of a carriage or wagon to keep the wheel from falling off. It’s a good metaphor: a linchpin is someone or something that keeps the wheels from falling off of an operation—they keep the whole thing working. It can also be spelled lynchpin. Example: Their point guard wasn’t their main scorer, but she was the linchpin to the team’s success, and they started to lose a lot of games after she was injured.

Etymology

Origin of linchpin

First recorded in 1350–1400; unexplained alteration of Middle English linpin, lynspin, equivalent to lyns, linch, lens, Old English lynis “axle-pin, axletree” (cognate with German Lünse ) + pin pin

Explanation

Literally, a linchpin is the pin that goes through the axle of a wheel to keep it in place, but linchpin can be used to mean an important part of anything, the thing that holds it all together. The linchpin is something that supports and holds another thing together. It’s the most important part of anything — eating well is the linchpin to staying healthy. A basketball team's most valuable player is the linchpin. The most crucial part of a plan is the linchpin. If something or someone is indispensable, she’s the linchpin. Take away the linchpin and everything falls apart.

Example Sentences

He will be among the negotiators at the helm of high-stakes talks already underway to renew the North American free trade accord, a linchpin of Mexico’s export-dominated economy.

From Los Angeles Times • Apr. 14, 2026

OpenAI, the linchpin of many AI deals, has shut down its Sora video app.

From Barron's • Mar. 25, 2026

TSA workers are a linchpin of U.S. airport security, scanning travelers and their bags before they can head to their gates.

From The Wall Street Journal • Mar. 21, 2026

Britain’s National Crime Agency later identified Coral as a linchpin of Russia’s oil market.

From The Wall Street Journal • Mar. 19, 2026

She thought about something Hazel had confided to her a few nights ago: I think Jason is the linchpin to Hera’s whole scheme.

From "Blood of Olympus" by Rick Riordan

Related Words

• essential
• foundation
• keystone
• mainstay
• pillar