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definitions

mainspring

[meyn-spring]
See more synonyms for mainspring on Thesaurus.com
noun
  1. the principal spring in a mechanism, as in a watch.
  2. the chief motive power; the impelling cause.

Origin of mainspring

First recorded in 1585–95; main1 + spring
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for mainspring

emotion, motivation, impulse, influence, idea, aim, intention, intent, rationale, consideration, passion, feeling, cause, provenance, element, motive, source, connection, ancestry, ancestor

Examples from the Web for mainspring

Historical Examples of mainspring

  • Perhaps this had originally been the mainspring of the understanding between them.

    Little Dorrit

    Charles Dickens

  • How's she goin' to cock that gun, an' the mainspring fifteen pounds resistance?'

    Faro Nell and Her Friends

    Alfred Henry Lewis

  • That need is the mainspring of life, the key to heaven, and the root of all evil.

    Olive in Italy

    Moray Dalton

  • The words were an echo of those which formed the mainspring of the Admiral's life.

  • For that was really the mainspring of her fantastic actions.

    The Good Soldier

    Ford Madox Ford

British Dictionary definitions for mainspring

mainspring

noun
  1. the principal power spring of a mechanism, esp in a watch or clock
  2. the chief cause or motive of something
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for mainspring
n.

1590s, of watches, clocks, etc., from main (adj.) + spring (n.3). Figurative use from 1690s.

Online Etymology Dictionary, © 2010 Douglas Harper