Merriam-Webster Logo
SINCE 1828
Menu
×

mainspring

noun main·spring \ ˈmān-ˌspriŋ \
|Updated on: 1 May 2018

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

See mainspring defined for English-language learners

See mainspring defined for kids

Examples of mainspring in a Sentence

  1. Agriculture is the mainspring of their economy.

Recent Examples of mainspring from the Web

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

See Words from the same year
NEW! Time Traveler

MAINSPRING Defined for English Language Learners

mainspring

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

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

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

Seen and Heard

What made you want to look up mainspring? Please tell us where you read or heard it (including the quote, if possible).

show hide

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

WORD OF THE DAY

notorious

play

widely and unfavorably known

Get Word of the Day daily email!

TRENDING NOW

  1. asylum 'protection from arrest and extradition given especially to political refugees'

  2. insubordinate 'disobedient to authority'

  3. promulgate 'to make known by open declaration'

  4. epochal 'momentous or unparalleled'

  5. clemency 'merciful treatment of someone who could be given harsh punishment'

SEE ALL

BROWSE DICTIONARY

mainspring

Test Your Vocabulary

Words for Summer: A Quiz

  • a-closeup-of-a-sunflower
  • Which of the following words means “of or relating to summer”?
True or False

Test your knowledge - and maybe learn something along the way.

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Words at Play

Ask the Editors

Word Games