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
From the M-W Editors
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.
13th Century
First Known Use of cornerstone
13th century
CORNERSTONE Defined for English Language Learners
cornerstone
playDefinition of cornerstone for English Language Learners
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: 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
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: something of basic importance
Learn More about cornerstone
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See words that rhyme with cornerstone Thesaurus: All synonyms and antonyms for cornerstone Spanish Central: Translation of cornerstone Nglish: Translation of cornerstone for Spanish speakers Britannica English: Translation of cornerstone for Arabic speakers Britannica.com: Encyclopedia article about cornerstone
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