decelerate

verb

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

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
(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

See All Synonyms & Antonyms in Thesaurus

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.
Looking ahead, Prestige Economics expects year-on-year Total CPI and Total PCE to decelerate in 2025. — Jason Schenker, Forbes, 20 Mar. 2025 Coresight Research predicted that U.S. retail sales will decelerate slightly in February and March as consumer pessimism and concerns over inflation continue to weigh on their minds. — Vicki M. Young, Sourcing Journal, 6 Mar. 2025 The category’s sales decelerated by about 4 percentage points sequentially in the fiscal third quarter, but company leaders blamed challenging weather and called out strength in its women’s apparel business. — Melissa Repko, CNBC, 26 Feb. 2025 February inflation cooled but remained elevated as total Consumer Price Index inflation decelerated to 2.8% from 3% and core CPI inflation decelerated to 3.1% from 3.3%. — Jason Schenker, Forbes, 12 Mar. 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

Rhymes for decelerate

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Browse Nearby Words

deceive oneself into thinking
decelerate
deceleration lane
See all Nearby Words

Cite this Entry

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

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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
(ˌ)dē-ˌsel-ə-ˈrā-shən How to pronounce decelerate (audio)
noun
decelerator
(ˈ)dē-ˈsel-ə-ˌrāt-ər How to pronounce decelerate (audio)
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
(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

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