O-ring

American  

[oh-ring] / ˈoʊˌrɪŋ /

noun

1. a ring of pliable material, as rubber or neoprene, used as a gasket: the failure of an O-ring caused the explosion that destroyed the space shuttle Challenger in 1986.

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O-ring British  

noun

1. a rubber ring used in machinery as a seal against oil, air, etc

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Etymology

Origin of O-ring

First recorded in 1945–50

Example Sentences

Ms. Vaughan argues that, over time, NASA’s work culture privileged risk-taking, such as launching at temperatures known to cause O-ring damage.

From The Wall Street Journal • Nov. 28, 2025

The company said an O-ring in the antilock brake motor shaft can lose sealing strength over time due to the presence of moisture, dirt and dissolved metals in the brake fluid, causing leaks.

From Washington Times • Sep. 27, 2023

It's an example of what economists call an O-ring technology, harking back to the rubber seals whose catastrophic failure caused the Space Shuttle Challenger disaster in 1986.

From Salon • Dec. 18, 2022

The fresh black-eyed pea is a wonder of markings all its own, with that deep purple-black O-ring in the same spot on every tiny little pale green pea.

From New York Times • Sep. 15, 2021

The Celestial bronze O-ring slipped out of Leo’s pliers and slid into the depths of the crawl space.

From "Blood of Olympus" by Rick Riordan