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.
In 2025 and 2026, this trend might decelerate, though, with a potentially looming recession that could further depress the demand for luxury watches. — Stéphane Jg Girod, Forbes.com, 9 Apr. 2025 The report showed average hourly earnings climbed at a firm pace from the prior month, but decelerated on an annual basis to the slowest rate since July. — Bloomberg, Mercury News, 4 Apr. 2025 Job growth – another big prop to the economy – continues, although at a decelerating rate. — Laurent Belsie, Christian Science Monitor, 2 Apr. 2025 The ride accelerates and decelerates like a roller coaster. — Ramsey Qubein, Forbes.com, 30 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 18 Apr. 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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