im·​pe·​tus ˈim-pə-təs How to pronounce impetus (audio)
: a driving force : impulse
: stimulation or encouragement resulting in increased activity
: 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

Impetus comes from the Latin verb impetere, meaning "to attack," which is a combination of the prefix in-, meaning "toward," with petere, meaning "to go to" or "to seek." Hence, 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
Recent Examples on the Web But catering to clients that are used to having their wishes realized sooner rather than later was also an impetus. Paige Reddinger, Robb Report, 27 Nov. 2023 The impetus for making the book entirely plant-based was to broaden people's repertoire and horizon. Megan Zhang, Saveur, 22 Nov. 2023 What was the impetus behind publishing your first book? Lily Moayeri, SPIN, 1 Nov. 2023 Luyendyk told me the impetus for Al-Powered Dates was feedback from users. Steven Aquino, Forbes, 13 Nov. 2023 Smarter KPIs can operate as an organizational GPS of sorts, streamlining decision-making and impetus across teams. François Candelon, Fortune, 10 Nov. 2023 Since then, a growing sense of paranoia has given Israel’s government the impetus to ramp up restrictions and surveillance in the West Bank, according to analysts and activists working in the region. WIRED, 7 Nov. 2023 Reflecting on Open Gaza now, the impetus to see Palestinians in Gaza as a source of life, capability, and possibility rather than as grim statistics has never been more urgent or important. Curbed, 20 Oct. 2023 While previous peace efforts had failed, the overwhelming impetus for a settlement came finally from an unlikely quarter when the tsunami of December 2004 devastated Aceh province, killing 170,000 people, making 500,000 homeless and prompting the combatants to return to negotiations. Alan Cowell, New York Times, 16 Oct. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'impetus.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

First Known Use

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

Time Traveler
The first known use of impetus was in 1641


Dictionary Entries Near impetus

Cite this Entry

“Impetus.” Dictionary, Merriam-Webster, Accessed 8 Dec. 2023.

Kids Definition


im·​pe·​tus ˈim-pət-əs How to pronounce impetus (audio)
: a driving force : impulse

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