keystone

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noun key·stone \ˈkē-ˌstōn\

Definition of keystone

  1. 1 :  the wedge-shaped piece at the crown of an arch that locks the other pieces in place — see arch illustration

  2. 2 :  something on which associated things depend for support <determination, a keystone of the puritan ethic — L. S. Lewis>

  3. 3 :  a species of plant or animal that produces a major impact (as by predation) on its ecosystem and is considered essential to maintaining optimum ecosystem function or structure

Examples of keystone in a sentence

  1. Tourism is the city's economic keystone.

  2. the keystone of his faith

Circa 1637

First Known Use of keystone

circa 1637

Other Architecture Terms


KEYSTONE Defined for English Language Learners

keystone

play
noun key·stone \ˈkē-ˌstōn\

Definition of keystone for English Language Learners

  • : a large stone at the top of an arch that locks the other stones in place

  • : something on which other things depend for support


KEYSTONE Defined for Kids

keystone

play
noun key·stone \ˈkē-ˌstōn\

Definition of keystone for Students

  1. 1 :  the wedge-shaped piece at the top of an arch that locks the other pieces in place

  2. 2 :  something on which other things depend for support



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