cornerstone

noun

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

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
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.
Self-awareness and emotional regulation are cornerstones of leadership effectiveness. Gamini Hewawasam, Forbes.com, 1 July 2025 Once the cornerstone of his political strength, President Donald Trump's base is showing signs of erosion. Martha McHardy, MSNBC Newsweek, 29 June 2025 The freedom to pass on one’s beliefs to the next generation is a cornerstone of any truly pluralistic society. Jeffrey S. Trimbath, Baltimore Sun, 29 June 2025 Security vendors and their AV products generally have access to the Windows kernel, the cornerstone of the operating system that sits between your hardware and most user applications. ArsTechnica, 27 June 2025 See All Example Sentences for cornerstone

Word History

First Known Use

13th century, in the meaning defined at sense 1

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

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Cite this Entry

“Cornerstone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cornerstone. Accessed 6 Jul. 2025.

Kids Definition

cornerstone

noun
cor·​ner·​stone ˈkȯr-nər-ˌstōn How to pronounce cornerstone (audio)
1
: a stone forming part of a corner in a wall
2
: something of basic importance
the cornerstone of our foreign policy

More from Merriam-Webster on cornerstone

Last Updated: - Updated example sentences
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