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 Inside, there are two mainplates, each of which holds a movement consisting of a mainspring, a cylinder, a comb and regulator. Roberta Naas, Forbes, 4 May 2022 The energy created by these thermal variations is connected to a mechanism that uses it to wind the mainspring. Carol Besler, Robb Report, 13 Apr. 2022 His musical collaboration with Parks is the personal, passionate mainspring of that transformation. Richard Brody, The New Yorker, 26 Apr. 2022 Cartier has created a platinum automatic skeleton watch in which the rotor houses the entire movement—mainspring, escapement, and all. Charles Curkin, ELLE Decor, 12 Apr. 2022 Her film’s ironies start with the title, because many of the movie’s viewers, like many of its interview subjects from the world of music, would rather not listen to Kenny G’s music at all—and their aversion is the mainspring of the film. Richard Brody, The New Yorker, 4 Dec. 2021 Between picturesque villages with draconian speed limits, the iX unwinds like a fine mainspring. Dan Neil, WSJ, 1 Oct. 2021 The Rolex Oyster Perpetual contained a kinetic semi-circular plate that utilized movement from the wearer’s arm to tension the mainspring, making manual winding unnecessary. Kyle Roderick, Forbes, 22 June 2021 The dial side also offers a peek at the open-worked barrel at 10 o’clock and the coiled mainspring, providing 72 hours of power reserve. Paige Reddinger, Robb Report, 10 Apr. 2021 See More

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.

First Known Use of mainspring

1591, in the meaning defined at sense 1

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Time Traveler for mainspring

Time Traveler

The first known use of mainspring was in 1591

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main squeeze

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Last Updated

15 May 2022

Cite this Entry

“Mainspring.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More Definitions for mainspring


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)

More from Merriam-Webster on mainspring Encyclopedia article about mainspring


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