im·pe·tus | \ˈim-pə-təs \

Definition of impetus 

1a(1) : a driving force : impulse

(2) : incentive, stimulus

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 was to perform a special show a few years ago -- a Fin Fest for Finnish expatriates in the U.S. -- in Arizona. Gary Graff, Billboard, "Tuomo & Markus Share 'Don't Shut Down Your Radio' From Debut Album: Premiere," 12 July 2018 The impetus was Russia’s annexation earlier that year of Crimea from Ukraine and Moscow’s stoking of military unrest in Ukraine’s east—along with longtime pressure from Washington, which Mr. Trump ratcheted up. Daniel Michaels, WSJ, "NATO, Under Fire From Trump, to Trumpet Its Heightened Readiness," 6 July 2018 The impetus was two-fold, the elder Kelenic said, explaining his original motivation just days after Jarred's first-round selection on June 4 and subsequent signing by the New York Mets. Jim Riccioli, Milwaukee Journal Sentinel, "Jarred Kelenic's success partly relied on training at Waukesha facilities built by his dad, who hopes he can help more athletes," 13 June 2018 Instead, the impetus is really on young designers and companies—and in-the-know consumers. Emily Farra, Vogue, "This Zero-Waste, Closed-Loop Company Will Revolutionize the Way You Buy T-Shirts," 29 May 2018 The impetus for the story and this whole investigation was actually my own experience with Morgan Freeman at a junket last year, for the movie Going In Style. Jayme Deerwester, USA TODAY, "Morgan Freeman's lawyer demands CNN retract story accusing actor of sexual misconduct," 29 May 2018 Krebs and her co-authors said the impetus for their clinical trial was the escalating opioid crisis, which now claims about 115 American lives each day, according to the Centers for Disease Control and Prevention. Karen Kaplan,, "For all their risks, opioids had no pain-relieving advantage in a yearlong clinical trial," 6 Mar. 2018 Smith's impending return was the impetus for the Astros' roster move on Sunday, optioning Cionel Perez back to Class AA after Yuli Gurriel returned from paternity leave. Chandler Rome, Houston Chronicle, "Astros' Joe Smith completes rehab assignment with Class AA," 1 July 2018 Would funds have been available without the impetus of an international spectacle? Warren Mabee, Smithsonian, "In a World Striving To Cut Carbon Emissions, Do the Olympics Make Sense?," 16 Feb. 2018

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

16 Oct 2018

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

: 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

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