1
a(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

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Before leaving for Tokyo, Jacobs spoke with WWD about his return to Japan and the impetus behind doing an exclusive partnership in Japan with Isetan. Lisa Lockwood, WWD, 14 Feb. 2025 The big impetus behind Pakistan was to present a more complete picture of Pakistani cuisine. Sonya Rehman, Forbes, 11 Feb. 2025 That, Seng said, was the impetus for the UIC project. Donna Vickroy, Chicago Tribune, 5 Feb. 2025 Report Regardless of who wins that job, there's no impetus for the Cubs to deal from their infield after the trade of Bellinger and the acquisition of outfielder Kyle Tucker in a blockbuster deal with the Houston Astros. Kristen Waggoner, Newsweek, 21 Jan. 2025 See all Example Sentences for impetus 

Word History

Etymology

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

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Dictionary Entries Near impetus

Cite this Entry

“Impetus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/impetus. Accessed 22 Feb. 2025.

Kids Definition

impetus

noun
1
a
: a driving force : impulse
b
2

More from Merriam-Webster on impetus

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