cor·​ner·​stone | \ ˈkȯr-nər-ˌstōn How to pronounce cornerstone (audio) \

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

Ashcroft made voter fraud, and the implementation of a photo ID requirement to vote to prevent fraud, a cornerstone of his successful 2016 campaign for secretary of state. Lindsay Wise, kansascity, "Voter fraud much greater threat than election hacking, Missouri's Jay Ashcroft says," 20 June 2018 Breed made her out-of-the-projects story a cornerstone of her campaign. Dominic Fracassa, San Francisco Chronicle, "Mark Leno concedes SF mayor’s race to London Breed," 13 June 2018 And there are Dak Prescott and Nick Fitzgerald at Mississippi State, the cornerstones of the Bulldogs offense over the past five years that Mullen turned into a competitor in the vicious SEC West. Jordan Mcpherson, miamiherald, "Gators' Dan Mullen wants to see 'massive strides' from QBs before naming a starter | Miami Herald," 9 May 2018 New Orleans would use that pick to select Davis, the new cornerstone of the franchise. William Guillory,, "Remembering the last time New Orleans won an NBA playoff game," 15 Apr. 2018 Mueller was also empowered by Rosenstein to investigate Manafort's payments from Ukrainian politicians, a cornerstone of the Trump adviser's decades-long lobbying career that has resulted in several financial criminal charges so far. CNN, "Read the DOJ memo authorizing Mueller to investigate potential Manafort collusion," 3 Apr. 2018 One cornerstone of her message is that older women can offer as much wisdom as their male counterparts. Alex Kuczynski, Town & Country, "Diane and Talita von Furstenberg Turn an American Empire into a Family Dynasty," 7 Feb. 2019 In a little under two years, the Women’s March has gone from a cornerstone of the #resistance to a controversial event filled with problematic figures. Molly Jong-fast, Glamour, "We’ve Outgrown the Women’s March. Here’s What Happens Next.," 18 Jan. 2019 At the same time, priests are seen as living representatives of Christ, with obedience to them another Catholic cornerstone. Tim Sullivan, The Seattle Times, "AP finds long history of nuns abused by priests in India," 1 Jan. 2019

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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Statistics for cornerstone

Last Updated

27 Mar 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).


to affect and impair by alcohol or a drug

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