keystone

noun

ˈkē-ˌstōn How to pronounce keystone (audio)
Definition of keystonenext
as in cornerstone
an immaterial thing upon which something else rests a sense of history is the keystone to the city's draw as a tourist destination

Synonyms & Similar Words

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Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of keystone The fest is a keystone event for Sandbox on the Beach, Santa Monica’s new civic plan for public events like the upcoming Super Bowl LXI and the LA28 Olympics and Paralympics. — Los Angeles Times, 16 July 2026 Hartford Bonanza is always meant to be a keystone summer event. — Christopher Arnott, Hartford Courant, 28 June 2026 Tales of what happened at Roswell have grown in the telling so that it’s now seen as a keystone event by many true believers in the alien origins of unidentified flying objects (UFOs). — Emma Gometz, Scientific American, 12 June 2026 Housing is the keystone that impacts multiple issues most important to San Jose’s residents. — Mercury News Editorial Board, Mercury News, 26 May 2026 See All Example Sentences for keystone
Recent Examples of Synonyms for keystone
  1. cornerstone
  2. basis
  3. foundation
  4. bedrock
Noun
  • Each became a cornerstone of Eighties country music, but Anderson didn’t stop there.
    — Joseph Hudak, Rolling Stone, 22 Oct. 2026
  • Temasek was among the cornerstone investors in optical-components manufacturer Zhongji Innolight's multibillion-dollar initial public offering in July.
    — Lee Ying Shan, CNBC, 22 Oct. 2026
Definition of cornerstone
Noun
  • For the technology leader responsible for keeping essential services running, these details provide a basis for assessing what protections exist and what happens in an extreme scenario.
    — Margot Edelman, Fortune, 23 Oct. 2026
  • Violence in the West Bank has surged in recent years as settlements have expanded, often backed by Israeli forces; attacks on farmers and communities who rely on the olive harvest for their livelihoods now come on a daily basis.
    — Jessie Yeung, CNN Money, 23 Oct. 2026
Definition of basis
Noun
  • The two nearly complete skeletons that serve as the foundation for the new research date to the Late Triassic period nearly 237 million years ago.
    — Tarini Mehta, Sacbee.com, 26 Oct. 2026
  • Felucca is the foundation for many other community firmware projects, transforming the FM-1 into a true multi-engine synth.
    — ArsTechnica, ArsTechnica, 26 Oct. 2026
Definition of foundation
Noun
  • His position put him on the wrong side of a bedrock progressive policy in one of the most liberal places in America.
    — Nathaniel Meyersohn, CNN Money, 25 Oct. 2026
  • Barnes is cold-based, and thus frozen directly onto the bedrock beneath it, which prevents it from sliding.
    — Jacek Krywko, ArsTechnica, 24 Oct. 2026
Definition of bedrock

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keys
keystone
keystones
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Cite this Entry

“Keystone.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/keystone. Accessed 27 Oct. 2026.

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Britannica.com: Encyclopedia article about keystone

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