Keystone
[ KEE-stohn ]
Part of speech: noun
Origin: English, 17th century
1 .
A central stone at the summit of an arch, locking the whole together.
2 .
The central principle or part of a policy, system, etc., on which all else depends.
Examples of Keystone in a sentence
" The last year’s monthly profits were the keystone of the CEO’s argument for a new sales approach. "
" The health of some species, such as elephants, is considered the keystone of an entire ecosystem. "
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About Keystone
“Keystone” is an architectural and building term formed in English by fusing the noun “key,” meaning both an object to open and close a lock and also a crucial step, with the noun “stone.”
Did you Know?
In order to complete the building of a stone arch, traditional masons place a final stone at the peak of the arch to connect all the other pieces while redistributing their weight. This is called a “keystone,” both because it is crucial to the integrity of the structure, and because without it, the arch cannot be locked together. Without a keystone, a traditional stone arch will collapse under its own weight. In modern English, a “keystone” refers to any central idea or value upon which other things are based. For example, fighting climate change is a keystone of most environmental policies.
