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

Definition of decelerate

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

Other Words from decelerate

deceleration \ (ˌ)dē-​ˌse-​lə-​ˈrā-​shən How to pronounce decelerate (audio) \ noun
decelerator \ (ˌ)dē-​ˈse-​lə-​rā-​tər How to pronounce decelerate (audio) \ noun

Synonyms & Antonyms for decelerate



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Examples of decelerate in a Sentence

she decelerated the car as we entered the school zone
Recent Examples on the Web Prices may also decelerate as producers catch up with demand, officials hope. Jeanna Smialek, New York Times, 5 Jan. 2022 Accelerate and decelerate gradually, and hold the handrails while doing so to give yourself extra stability. Washington Post, 4 Nov. 2021 Hyundai has refined that technology for the Ioniq 5; the feature offers four increasing levels of lift-off regen that decelerate the EV at 0.1 G, 0.15 G, 0.2 G, or a one-pedal mode that regens at almost 0.3 G. Jonathan M. Gitlin, Ars Technica, 16 Dec. 2021 Given the rapid deceleration in M2 since September (see table and shown on chart with a 9-month lag), if the relationship continues to hold, the growth in the CPI will decelerate going forward. Robert Barone, Forbes, 12 Dec. 2021 Growth will probably decelerate further for the remainder of 2021 and into early 2022. Nathaniel Taplin, WSJ, 15 Nov. 2021 Growth will slow to a 4.3 percent pace next year and then decelerate to 2.5 percent in 2023, the commission said. Liz Alderman,, 11 Nov. 2021 Zillow’s house-flipping shutdown in part probably indicates the firm’s view of rising risks that prices might decline or decelerate more quickly on its large outstanding inventory. Phillip Molnar, San Diego Union-Tribune, 12 Nov. 2021 Forecasters expect growth to decelerate further if the financing curbs stay in place. Joe Mcdonald, ajc, 21 Oct. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'decelerate.' 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 decelerate

1899, in the meaning defined at transitive sense 1

History and Etymology for decelerate

de- + accelerate

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Time Traveler for decelerate

Time Traveler

The first known use of decelerate was in 1899

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Dictionary Entries Near decelerate

deceive oneself into thinking


deceleration lane

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Statistics for decelerate

Last Updated

18 Jan 2022

Cite this Entry

“Decelerate.” Dictionary, Merriam-Webster, Accessed 29 Jan. 2022.

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More Definitions for decelerate



English Language Learners Definition of decelerate

: to move slower : to lose speed
: to cause (something) to happen more slowly


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

Kids Definition of decelerate

: to slow down The car decelerated at the yellow light.


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

Medical Definition of decelerate

transitive verb

: to reduce the speed of : slow down

intransitive verb

: to move at decreasing speed

Other Words from decelerate

deceleration \ (ˌ)dē-​ˌsel-​ə-​ˈrā-​shən How to pronounce decelerate (audio) \ noun

More from Merriam-Webster on decelerate

Nglish: Translation of decelerate for Spanish Speakers

Britannica English: Translation of decelerate for Arabic Speakers


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