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
  • The Spurs believe the most imposing version of their defensive cornerstone has yet to arrive.
    — Jeff McDonald, San Antonio Express-News, 16 Oct. 2026
  • Since its introduction, hydroxyurea has become a cornerstone of sickle cell disease treatment that has helped thousands successfully manage their condition.
    — Steven Ross Johnson, CNBC, 16 Oct. 2026
Definition of cornerstone
Noun
  • Halpin watched the ball clear the wall in right-center then launched his bat over his head and into the sky before rounding the bases.
    — Arkansas Online, Arkansas Online, 16 Oct. 2026
  • Brewers third baseman David Hamilton rounds the bases after hitting a home run in the ninth inning.
    — Greg Rosenstein, NBC news, 16 Oct. 2026
Definition of basis
Noun
  • Its foundation is HiNAS Prime, an autonomous navigation system developed by Avikus, HD Hyundai’s autonomous navigation subsidiary.
    — Aamir Khollam, Interesting Engineering, 20 Oct. 2026
  • They're used in primers, foundations, and hair serums for a slick application.
    — Tracy Middleton, Allure, 19 Oct. 2026
Definition of foundation
Noun
  • Much of its ice rests on bedrock below sea level, while its floating ice shelves help regulate how quickly ice flows toward the sea.
    — Kaif Shaikh, Interesting Engineering, 17 Oct. 2026
  • The Chiefs’ offense hit its bedrock that night, with Mahomes firing 10 straight incompletions in a loss that all but ended their playoff hopes.
    — Sam McDowell October 16, Kansas City Star, 16 Oct. 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 20 Oct. 2026.

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Britannica.com: Encyclopedia article about keystone

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