decelerate

verb

de·​cel·​er·​ate (ˌ)dē-ˈse-lə-ˌrāt How to pronounce decelerate (audio)
decelerated; decelerating

transitive verb

1
: to reduce the speed of : slow down
decelerate a car
2
: to decrease the rate of progress of
decelerate growth
decelerate soil erosion

intransitive verb

: to move at decreasing speed
deceleration noun
decelerator noun

Examples of decelerate in a Sentence

she decelerated the car as we entered the school zone
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.
In the first six months, the Stone Island DTC channel grew by 7 percent to 99.1 million euros, decelerating in the second quarter amid a generally more challenging global operating environment. Luisa Zargani, Footwear News, 23 July 2025 Security footage shows that the multimillion-dollar jet accelerated on the runway but suddenly decelerated and overran the end of the runway, the report said. Maritza Dominguez, AZCentral.com, 16 July 2025 The former uses more juice, while the latter misses the full effect of regenerative braking, which recovers energy that would otherwise be lost while decelerating and braking. Jim Gorzelany, Forbes.com, 8 July 2025 Growth in the global contract logistics market is expected to decelerate in 2025, with the industry set to expand 3.3 percent to 305.4 million euros ($359.3 million), down from 3.6 percent last year. Glenn Taylor, Sourcing Journal, 1 July 2025 See All Example Sentences for decelerate

Word History

Etymology

de- + accelerate

First Known Use

1899, in the meaning defined at transitive sense 1

Time Traveler
The first known use of decelerate was in 1899

Cite this Entry

“Decelerate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/decelerate. Accessed 29 Jul. 2025.

Kids Definition

decelerate

verb
de·​cel·​er·​ate (ˈ)dē-ˈsel-ə-ˌrāt How to pronounce decelerate (audio)
decelerated; decelerating
: to move or cause to move at decreasing speed : slow down
deceleration noun

Medical Definition

decelerate

verb
de·​cel·​er·​ate (ˈ)dē-ˈsel-ə-ˌrāt How to pronounce decelerate (audio)
decelerated; decelerating

transitive verb

: to reduce the speed of : slow down

intransitive verb

: to move at decreasing speed
deceleration noun

More from Merriam-Webster on decelerate

Last Updated: - Updated example sentences
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