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 of mainspring from the Web
The mainspring of this imagined future clash is not race and slavery, but science and the environment.
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.
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
MAINSPRING Defined for English Language Learners
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
Definition of mainspring for Students
: the principal spring in a mechanical device (as a watch or clock)
Seen and Heard
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