main·​spring | \ ˈmān-ˌspriŋ How to pronounce mainspring (audio) \

Definition of mainspring

1 : the chief spring in a mechanism especially of a watch or clock
2 : the chief or most powerful motive, agent, or cause

Examples of mainspring in a Sentence

Agriculture is the mainspring of their economy.
Recent Examples on the Web The piece is equipped with a constant force mechanism called a remontoire that controls the heartbeat of the watch, transferring power between the mainspring and escapement to ensure its stability in timekeeping. Victoria Gomelsky, New York Times, "A Collection of Female Watch Collectors," 8 Mar. 2020 There have been many terrific magazines devoted to movies, but only one such magazine is both a mainspring of the history of the art form and an ongoing meme: Cahiers du Cinéma. Richard Brody, The New Yorker, "What’s at Stake in the Takeover of Cahiers du Cinéma," 6 Mar. 2020 Intelligent discontent is the mainspring of civilization. Matthew De Silva, Quartz, "Why crypto hoaxes are so successful," 26 Sep. 2019 Hatidze’s solitude is one of the film’s prime subjects and also its dramatic mainspring, and its details and practicalities are merely hinted at, and utterly unexplored, throughout. Richard Brody, The New Yorker, "“Honeyland,” Reviewed: A Gripping, Frustrating Documentary About a Beekeeper’s Fragile Isolation," 1 Aug. 2019 In the Type 390, the movement is arranged so that the gear trains lie in layers, from right to left, with the mainspring at one end and the tourbillon at the other., "A $300,000 Watch for Your $3.26 Million Sports Car," 3 Apr. 2018 In a conventional watch gear train, gears downstream in the power flow from the mainspring barrel turn more quickly than the gears that drive them., "A $300,000 Watch for Your $3.26 Million Sports Car," 3 Apr. 2018 The show’s mainspring and title song amounts to little more than a kvetch. Lily Janiak, San Francisco Chronicle, "Not much of a ‘Saturday Night’ except for Sondheim devotees," 2 Apr. 2018 This paranoia was the mainspring for Nixon’s attack on the constitutional order. Jeet Heer, New Republic, "Trump’s Cult of Personality Takes Paranoia to the Next Level," 26 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mainspring.' 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 mainspring

1591, in the meaning defined at sense 1

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The first known use of mainspring was in 1591

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Cite this Entry

“Mainspring.” Dictionary, Merriam-Webster, Accessed 1 Mar. 2021.

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More Definitions for mainspring



English Language Learners Definition of mainspring

: the most important spring in a watch or clock
: the most important or powerful cause or part of something


main·​spring | \ ˈmān-ˌspriŋ How to pronounce mainspring (audio) \

Kids Definition of mainspring

: the principal spring in a mechanical device (as a watch or clock)

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