keystone

noun

key·​stone ˈkē-ˌstōn How to pronounce keystone (audio)
1
: the wedge-shaped piece at the crown of an arch that locks the other pieces in place see arch illustration
2
: something on which associated things depend for support
determination, a keystone of the puritan ethicL. S. Lewis
3
or keystone species : a species of plant or animal that produces a major impact (as by predation) on its ecosystem and is considered essential to maintaining optimum ecosystem function or structure

Examples of keystone in a Sentence

Tourism is the city's economic keystone. the keystone of his faith
Recent Examples on the Web The account of how Yentl came to be falls smack in the middle of Streisand’s new, nearly 1,000-page memoir, My Name Is Barbra, and for that reason alone is an important keystone for understanding her. Gal Beckerman, The Atlantic, 7 Nov. 2023 This portable projector can also be used outside and has four-point keystone correction and Bluetooth compatibility. Margaret Drake, Rolling Stone, 26 Sep. 2023 Go on a beginner bird-watching walk at Malibu Lagoon, learn about keystone species at Carpinteria State Beach, take a hike at Chino Hills State Park, do sunset yoga at the historic Adamson House and more. Dakota Kim, Los Angeles Times, 15 June 2023 For the keystones about prompting of personas in generative AI, see the link here and the link here. Lance Eliot, Forbes, 11 Feb. 2024 These Falcon Heavy flights will cut across NASA's portfolio of robotic space missions, dispatching probes deep into the Solar System, deploying a flagship-class astronomical observatory, sending up a weather satellite, and launching the keystone to NASA's Gateway mini-space station around the Moon. Stephen Clark, Ars Technica, 13 Oct. 2023 Taken altogether, the speaker lineup might indicate a returning interest in third-party licensing, as keystone studios look to juice sales revenue, complementing the B2C model rather than competing with it. Ben Croll, Variety, 12 Oct. 2023 The rollback also comes as political campaigning for the United States 2024 presidential election ramps up, and concerns about the spread of misinformation online remains a keystone issue ahead of the US vote. Catherine Thorbecke, CNN, 27 Sep. 2023 Early childhood development has long been a keystone of Princess Kate’s royal world, and her back-to-back engagements shed light on the importance of loving relationships for children who have experienced adversity, trauma, or bereavement. Janine Henni, Peoplemag, 25 May 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'keystone.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

circa 1637, in the meaning defined at sense 1

Time Traveler
The first known use of keystone was circa 1637

Dictionary Entries Near keystone

Cite this Entry

“Keystone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/keystone. Accessed 19 Mar. 2024.

Kids Definition

keystone

noun
key·​stone ˈkē-ˌstōn How to pronounce keystone (audio)
1
: the wedge-shaped piece at the top of an arch that locks the other pieces in place
2
: something on which other things depend

More from Merriam-Webster on keystone

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