impetus
Americannoun
-
a moving force; impulse; stimulus.
The grant for building the opera house gave impetus to the city's cultural life.
- Synonyms:
- boost, spur, stimulation
-
(broadly) the momentum of a moving body, especially with reference to the cause of motion.
noun
-
an impelling movement or force; incentive or impulse; stimulus
-
physics the force that sets a body in motion or that tends to resist changes in a body's motion
Other Word Forms
Etymology
Origin of impetus
First recorded in 1650–60; from Latin: “an attack,” literally, “a rushing into,” perhaps by haplology from unattested impetitus (though the expected form would be unattested impetītus; see appetite), equivalent to impetī-, variant stem of impetere “to attack” ( im- im- 1 + petere “to make for, assault”) + -tus suffix of verb action
Explanation
An impetus is the force behind something, whether it's a boulder rolling down a hill or a person making a decision. Very little would get done if there were no such thing as an impetus: an impetus is some kind of force that gets something or somebody moving. If you push a car that's out of gas, you're the impetus that's getting it moving. An impetus doesn't have to be physical. Advertisers hope their commercials will be an impetus to buy the product.
Vocabulary lists containing impetus
The Vocabulary.com Top 1000
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"Remarks at the Dedication of the Aerospace Medical Health Center," Vocabulary from the speech
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A Thousand Splendid Suns
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The impetus for the order was Anthropic’s Mythos model.
From Barron's • Jun. 2, 2026
In the past, I have assumed that letting people know what I do would be an impetus for them to reach out to me if they ever have a financial need or question.
From MarketWatch • May 29, 2026
Zvezda Stankova, a teaching professor in the Berkeley mathematics department who is one of the letter’s lead organizers, said the impetus to publicly speak out came in part from her own classrooms.
From Los Angeles Times • May 27, 2026
That friction provided the impetus for Peter Shaffer’s Tony award-winning play “Amadeus,” which became a hit movie directed by Milos Forman in 1984.
From Salon • May 16, 2026
A new impetus for the project had emerged: fears of a shortage of uranium ore, the raw material for the production of plutonium bomb cores.
From "Big Science" by Michael Hiltzik
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
