cor·​ner·​stone | \ ˈkȯr-nər-ˌstōn \

Definition of cornerstone

1 : a stone forming a part of a corner or angle in a wall specifically : such a stone laid at a formal ceremony
2 : a basic element : foundation a cornerstone of foreign policy

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Examples of cornerstone in a Sentence

Officials held a ceremony to lay the cornerstone for a new library. Trust is the cornerstone of their relationship.

Recent Examples on the Web

Whether or not the 62-year-old Molitor could have done more, the 2018 season was a mess for center fielder Byron Buxton and third baseman Miguel Sano, the two players long groomed to be the franchise cornerstones. Dave Campbell, The Seattle Times, "Twins hire ex-Rays player, coach Rocco Baldelli as manager," 25 Oct. 2018 Miller came into to Columbus for four-star forward Jerome Hunter, right now the cornerstone of Indiana's 2018 recruiting class. Bill Landis,, "Chris Holtmann vs. Archie Miller: Unavoidable comparisons for Ohio State basketball fans, and a new Big Ten rivalry," 30 Jan. 2018 Marketing and ad sales are a cornerstone of business on the web. Eric Limer, Popular Mechanics, "Tech Companies Shouldn't Make Us Trust Them, At All," 11 Jan. 2019 Chris Jones projects a cornerstone type player on the Chiefs’ interior line who is working on becoming a force on the defense. Blair Kerkhoff, kansascity, "After a 'kind of silent' year, Chris Jones is leading the Chiefs' new defensive players," 15 June 2018 Jaylen Brown, who turns 22 in October, is a rising star who could be a cornerstone player for the Spurs for years to come. Tom Orsborn, San Antonio Express-News, "Potential trade partners for Leonard will line up on both coasts," 15 June 2018 Although the Diamondbacks would likely have to pay more than the $2.6 million slot value to land the LSU commit, Turang offers the skill set of a future cornerstone player and could see his slide end here. Richard Morin, azcentral, "MLB mock draft 1.0: Valley high-school stars Matthew Liberatore, Nolan Gorman in top 10," 18 May 2018 Both Decker and Davis were immediate starters as rookies and appear to be cornerstone players going forward. Dave Birkett, Detroit Free Press, "NFL draft: Detroit Lions GM won't eliminate any position from list," 19 Apr. 2018 Something inside Cowboys owner Jerry Jones must twitch at the thought of releasing a franchise cornerstone player in a timely manner. Conor Orr,, "Where Will Dez Bryant Play Next?," 13 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cornerstone.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of cornerstone

13th century, in the meaning defined at sense 1

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Last Updated

13 Feb 2019

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Time Traveler for cornerstone

The first known use of cornerstone was in the 13th century

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English Language Learners Definition of cornerstone

: a stone that forms part of a corner in the outside wall of a building and that often shows the date when the building was built
: something of basic importance

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Comments on cornerstone

What made you want to look up cornerstone? Please tell us where you read or heard it (including the quote, if possible).


excited commotion or publicity

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