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.
According to an investigation done by the Wall Street Journal, Meta with its 3 billion users is increasingly a cornerstone of the internet fraud economy. Steve Weisman, Forbes.com, 21 June 2025 Our commitment is to ensure that Balboa Park remains accessible to everyone, regardless of their economic standing, and free parking is a cornerstone of that commitment. Jessica Hanson York, San Diego Union-Tribune, 20 June 2025 The winter witnessed them trade their best player before allowing a franchise cornerstone to sign elsewhere. Chandler Rome, New York Times, 18 June 2025 Members of the congregation placed important documents and the history of the church in a copper box embedded in the cornerstone, though only a few of the charter members who organized the congregation in 1858 were living and present at the ceremony, historical documents said. Michelle Mullins, Chicago Tribune, 18 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

Browse Nearby Words

Cite this Entry

“Cornerstone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cornerstone. Accessed 25 Jun. 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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