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cornerstone

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noun cor·ner·stone \-ˌstōn\

Simple 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of cornerstone

  1. 1 :  a stone forming a part of a corner or angle in a wall; specifically :  such a stone laid at a formal ceremony

  2. 2 :  a basic element :  foundation <a cornerstone of foreign policy>

Examples of cornerstone in a sentence

  1. Officials held a ceremony to lay the cornerstone for a new library.

  2. Trust is the cornerstone of their relationship.



13th Century

First Known Use of cornerstone

13th century

Other Building Terms



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