- The definition of a cornerstone is a stone at the corner of a building, or a basic, essential part of something.
- An example of a cornerstone is the first piece of stone placed for a new building, often inscribed with the date to commemorate the occasion.
- An example of a cornerstone is the belief by Christians in Christ as the Son of God.
cornerstone definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
- a stone that forms part of the corner of a building; esp., a foundation stone of this kind, often inscribed, laid at a ceremony that marks the beginning of building
- the basic, essential, or most important part; foundation
Origin: Middle English
cornerstone definition by American Heritage Dictionary
The American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
also corner stonenoun
- a. A stone at the corner of a building uniting two intersecting walls; a quoin.b. Such a stone, often inscribed, laid at a ceremony marking the origin of a building.
- An indispensable and fundamental basis: the cornerstone of an argument.