mainspring

play

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

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Examples of mainspring in a Sentence

Agriculture is the mainspring of their economy.

Recent Examples of mainspring from the Web

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.

First Known Use of mainspring

1591

MAINSPRING Defined for English Language Learners

mainspring

play

noun

Definition of mainspring for English Language Learners

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

MAINSPRING Defined for Kids

mainspring

play

noun main·spring \ ˈmān-ˌspriŋ \

Definition of mainspring for Students

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

Learn More about mainspring

See words that rhyme with mainspring Britannica.com: Encyclopedia article about mainspring

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mainspring

Definition of mainspring

Examples of mainspring in a Sentence

Recent Examples of mainspring from the Web

First Known Use of mainspring

MAINSPRING Defined for English Language Learners

mainspring

Definition of mainspring for English Language Learners

MAINSPRING Defined for Kids

mainspring

Definition of mainspring for Students

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Examples of mainspring in a Sentence

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First Known Use of mainspring

MAINSPRING Defined for English Language Learners

mainspring

Definition of mainspring for English Language Learners

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Definition of mainspring for Students

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