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
  • This encouragement has been one of the cornerstones of Wilson’s season.
    — Julia Poe, Chicago Tribune, 30 Oct. 2026
  • The Titans, on the other hand, are 1-6 and have traded away one of their franchise cornerstones.
    — Ryan Canfield OutKick, FOXNews.com, 29 Oct. 2026
Definition of cornerstone
Noun
  • The defense trial accounts of bias were connected to Weeks’ rulings, which were within his discretion and not a basis for recusal, prosecutors argued.
    — Emerson Clarridge, Fort Worth Star-Telegram, 31 Oct. 2026
  • The combination of large-scale pre-training, distributed post-training and feedback-driven learning after deployment forms the basis of GO-3 Preview.
    — Jijo Malayil, Interesting Engineering, 30 Oct. 2026
Definition of basis
Noun
  • Fourier’s experience with humanoid robots provided a foundation for the project.
    — Jijo Malayil, Interesting Engineering, 2 Nov. 2026
  • As the initiative develops, these criteria could provide a foundation for future discussions about common benchmarks or guidelines, ideally involving stakeholders from across the industry.
    — Angela Velasquez, Footwear News, 2 Nov. 2026
Definition of foundation
Noun
  • But, mostly, remain with the bedrock of what fueled the Big Three success more than a decade ago and then the Heat’s NBA Final trips success thereafter.
    — Ira Winderman, Sun Sentinel, 1 Nov. 2026
  • Whatever one calls it, this permitting bill stands to degrade key provisions of bedrock laws, including the ESA, Clean Water Act, and National Environmental Policy Act.
    — Elizabeth Neville, The Orlando Sentinel, 1 Nov. 2026
Definition of bedrock

Browse Nearby Words

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 6 Nov. 2026.

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Britannica.com: Encyclopedia article about keystone

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