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

Embraer, which is based in the state of São Paulo, has been a cornerstone of Brazil’s manufacturing sector for almost 50 years. Robert Wall, WSJ, "Boeing to Take Over Embraer’s Commercial-Jet Business," 5 July 2018 Natural selection has been a cornerstone of evolutionary theory ever since Darwin. John Rennie, WIRED, "This Mutation Math Shows How Life Keeps on Evolving," 1 July 2018 Venezuela has about 8 million school children in total, and free education was a cornerstone of ex-President Hugo Chávez's 1999-2013 socialist rule of the OPEC nation. Vivian Sequera And Francisco Aguilar, The Christian Science Monitor, "As economic crisis worsens, schools empty in Venezuela," 25 Apr. 2018 Such coalition building has long been seen as a cornerstone of democracy. Benjamin Toff, Washington Post, "How worried are you about an impending trade war? That might depend on what your fellow party members think," 12 July 2018 That came just a few months after its cornerstone was laid, a summer day when a crowd of at least 10,000 processed through the neighborhood to mark the occasion, according to a Boston Globe account. Emily Williams,, "Business booming at dollar store on Catholic church site," 30 June 2018 LaVine was viewed as the cornerstone of last June’s trade of Jimmy Butler to the Timberwolves. K.c. Johnson,, "Bulls plan patient approach in free agency, will focus first on re-signing Zach LaVine and David Nwaba," 30 June 2018 Duval was known as a friend to all, teaching the D.A.R.E Program for several years and acting as a cornerstone to the building of the Colchester Police Department. Courant Community, "Community News For The Colchester Edition," 21 May 2018 Naloxone, which is a drug that can keep drug users alive by reversing opioid overdoses, is viewed by many as the cornerstone of the harm-reduction approach to the epidemic. NBC News, "Surgeon general wants Naloxone widely on hand. Is this feasible?," 18 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

6 Nov 2018

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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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