mainspring

noun

main·spring | \ ˈmān-ˌspriŋ

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

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. — Bloomberg.com, "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. — Bloomberg.com, "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 At the end of the day, the headline is going to be what Jane Fleming Kleeb, the chairman of the Nebraska Democratic Party and the mainspring of the opposition to the project, said after the hearings adjourned on Thursday afternoon. — Charles P. Pierce, Esquire, "Why the Keystone Battle, and Others Like It, Will Never End," 10 Aug. 2017 The mainspring of this imagined future clash is not race and slavery, but science and the environment. — The Washington Post, OregonLive.com, "Omar El Akkad's 'American War' blends 19th-century hatreds, 21st-century weapons," 30 May 2017 To build the Reference, Patek adapted self-winding technology from its rival, Rolex: a new mechanism that spun around the mainspring instead of swinging back and forth. — Jonathon Keats, WIRED, "Design: Evolution of the Self-Winding Wristwatch," 11 Nov. 2009

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.