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.
Tyrer also was the left tackle on the AFL All-Time Team and a cornerstone of three franchise AFL titles and the Super Bowl IV champions. Kansas City Star, 17 Oct. 2025 The brittle cornerstone of a decades-old player-development system suddenly crumbled, bringing the rest of the city game down with it. Luke Cyphers, Sportico.com, 17 Oct. 2025 The Classic Knit The cornerstone of fall dressing is the crewneck sweater–versatile, comfortable, and endlessly re-wearable. Minty Mellon, Vogue, 17 Oct. 2025 Ryst highlighted a couple of French institutions that have embraced YouTube as a cornerstone of their digital strategy. Lise Pedersen, Variety, 17 Oct. 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 23 Oct. 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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