im·​pe·​tus | \ ˈim-pə-təs How to pronounce impetus (audio) \

Definition of impetus

1a(1) : a driving force : impulse
b : stimulation or encouragement resulting in increased activity
2 : the property possessed by a moving body in virtue of its mass and its motion used of bodies moving suddenly or violently to indicate the origin and intensity of the motion

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Impetus Has Latin Roots

You already have plenty of incentive to learn the origin of "impetus," so we won't force the point. "Impetus" comes from Latin, where it means "attack or assault"; the verb "impetere" was formed by combining the prefix in- with petere, meaning "to go to or seek." "Petere" also gives us other words suggesting a forceful urging or momentum, such as "appetite," "perpetual," and "centripetal." "Impetus" describes the kind of force that encourages an action ("the impetus behind the project") or the momentum of an action already begun ("the meetings only gave impetus to the rumors of a merger").

Examples of impetus in a Sentence

In a revealing comment, Mr. Updike says an impetus for Rabbit, Run was the "threatening" success of Jack Kerouac's On the Road, the signature book of the 1950s Beat Generation, and its frenetic search for sensation. — Dennis Farney, Wall Street Journal, 16 Sept. 1992 But 1939 gave new impetus to the Western with the Cecil B. de Mille railway epic Union Pacific, John Ford's skillful and dramatic Stagecoach,  … and George Marshall's classic comic Western, Destry Rides Again. — Ira Konigsberg, The Complete Film Dictionary, 1987 … new techniques of navigation and shipbuilding enlarged trade and the geographical horizon; newly centralized power absorbed from the declining medieval communes was at the disposal of the monarchies and the growing nationalism of the past century gave it impetus — Barbara W. Tuchman, The March of Folly, 1984 His discoveries have given impetus to further research. the reward money should be sufficient impetus for someone to come forward with information about the robbery
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Recent Examples on the Web

The impetus for much of his work was the Federal Aid Highway Act of 1956, which authorized a 41,000-mile road network to connect the nation. Joy Wallace Dickinson,, "Through muck and mayhem, he paved path to the future," 15 Sep. 2019 The impetus for today's crisis is the result of a number of factors — from shrinking union membership, to changes in regulatory policies and the stock market losses during the Great Recession. CNN, "America is facing a pension crisis. Retirees will pay the price if we don't act now," 14 Aug. 2019 The impetus for the change from a detention to a retention basin is twofold. John Benson,, "Parma Heights considers ‘sexier’ changes to Nathan Hale Park basin design," 26 July 2019 The impetus was a detailed investigation of the lead crisis in Santa Ana by former ThinkProgress investigative reporter Yvette Cabrera. Ben Brazil, Daily Pilot, "Toxic soil in Santa Ana? Community groups are working with UC Irvine to find out," 23 Aug. 2019 While the amicus brief filed by Whitehouse and his fellow senators may offend some with its feisty tone, the impetus for it is one that many Americans, concerned with the proliferation of mass shootings and gun violence, will no doubt understand. Ephrat Livni, Quartz, "A gun law case before the US Supreme Court has Americans up in arms," 17 Aug. 2019 But the impetus for the policy was to curb suicides by firearm, not mass gun violence. Rubén Rosario, Twin Cities, "Rosario: On mental illness, dissing prosecutors and some bandwagon Twins fans …," 17 Aug. 2019 In Antoine Griezmann, Atletico have not just lost their top scorer, and the only player to even get into double figures last season, but also the source of their attacking impetus., "Atletico Madrid, Real Madrid or Barcelona: Assessing Each of the La Liga Title Favourites," 3 Aug. 2019 If the impetus of Taffy Brodesser-Akner’s whip-smart, gleefully scatological debut is Toby’s newfound freedom, his soon-to-be ex-wife, Rachel, is the kryptonite. Leah Greenblatt,, "Taffy Brodesser-Akner spins a Great American Divorce Novel in her terrific debut: EW review," 19 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'impetus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of impetus

1641, in the meaning defined at sense 1a(1)

History and Etymology for impetus

Latin, assault, impetus, from impetere to attack, from in- + petere to go to, seek — more at feather

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Statistics for impetus

Last Updated

18 Sep 2019

Look-up Popularity

Time Traveler for impetus

The first known use of impetus was in 1641

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More Definitions for impetus



English Language Learners Definition of impetus

: a force that causes something (such as a process or activity) to be done or to become more active
technical : a force that causes an object to begin moving or to continue to move

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More from Merriam-Webster on impetus

Thesaurus: All synonyms and antonyms for impetus

Spanish Central: Translation of impetus

Nglish: Translation of impetus for Spanish Speakers

Britannica English: Translation of impetus for Arabic Speakers

Comments on impetus

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formidable, illustrious, or eminent

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