keystone

noun
key·​stone | \ ˈkē-ˌstōn How to pronounce keystone (audio) \

Definition of keystone

1 : the wedge-shaped piece at the crown of an arch that locks the other pieces in place — see arch illustration
2 : something on which associated things depend for support determination, a keystone of the puritan ethic— L. S. Lewis
3 or keystone species : 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

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Examples of keystone in a Sentence

Tourism is the city's economic keystone. the keystone of his faith
Recent Examples on the Web Somewhere nearby, carefully hidden from the public, is the Ozark chinquapin tree, once a keystone Ozark forest species. Robert Langellier, National Geographic, "A legendary Ozark chestnut tree, thought extinct, is rediscovered," 24 June 2019 The keystone project there involved a $15-million building with apartments and shops that the Finch Group built on East 105th at Ashbury Avenue. Robert Higgs, cleveland, "Cleveland, neighborhood non-profit target 14-block, East Side commercial strip for growing new businesses," 17 Feb. 2020 The progress nine months out from the 2020 election puts the Trump administration over budget and behind schedule on the president’s keystone campaign promise to build a wall on the U.S.-Mexico border. Anna Giaritelli, Washington Examiner, "Trump vows to put up 'substantially more than 500 miles' of border wall by early 2021," 4 Feb. 2020 But, in recent years, this keystone property has fallen into steep decline, with profits falling 69 percent in three years. BostonGlobe.com, "WASHINGTON — President Trump has awarded the 2020 G-7 Summit of world leaders to his own private company, scheduling the summit for June at his Trump Doral golf resort outside Miami, the White House announced on Thursday.," 18 Oct. 2019 Lubchenco, the administrator of the National Oceanic Atmospheric Administration from 2009 to 2013, saw over the years the impact that Paine’s keystone species concept had on policies related to fisheries management. Adam Hadhazy, Discover Magazine, "The Top 10 Science Experiments of All Time," 10 Oct. 2019 Yet in humanity – the keystone species for fire on Earth – those two arenas of earthly burning, like smoke from separate fires drawn into a single convective column, are merging. Stephen Pyne, The Conversation, "California wildfires signal the arrival of a planetary fire age," 1 Nov. 2019 Yet in humanity—the keystone species for fire on Earth—those two arenas of earthly burning, like smoke from separate fires drawn into a single convective column, are merging. Stephen Pyne, Quartz, "The Earth could be entering a planetary fire age," 10 Nov. 2019 The launch of a new subscription video streaming service was a keystone in AT&T's $85 billion deal for Time Warner, CNN's parent company. Brian Stelter, CNN, "With HBO Max, AT&T is launching a streaming service that 'a lot of people said couldn't be done'," 28 Oct. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'keystone.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of keystone

circa 1637, in the meaning defined at sense 1

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Time Traveler for keystone

Time Traveler

The first known use of keystone was circa 1637

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Statistics for keystone

Last Updated

22 Feb 2020

Cite this Entry

“Keystone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/keystone. Accessed 28 Feb. 2020.

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More Definitions for keystone

keystone

noun
How to pronounce keystone (audio)

English Language Learners Definition of keystone

: 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

noun
key·​stone | \ ˈkē-ˌstōn How to pronounce keystone (audio) \

Kids Definition of keystone

1 : the wedge-shaped piece at the top of an arch that locks the other pieces in place
2 : something on which other things depend for support

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More from Merriam-Webster on keystone

Thesaurus: All synonyms and antonyms for keystone

Rhyming Dictionary: Words that rhyme with keystone

Spanish Central: Translation of keystone

Nglish: Translation of keystone for Spanish Speakers

Britannica.com: Encyclopedia article about keystone

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