acceleration

noun

ac·​cel·​er·​a·​tion ik-ˌse-lə-ˈrā-shən How to pronounce acceleration (audio)
(ˌ)ak-
Synonyms of acceleration
1
a
: the act or process of moving faster or happening more quickly : the act or process of accelerating
rapid acceleration
the acceleration of economic growth
b
: ability to accelerate
a car with good acceleration
2
physics : the rate of change of velocity with respect to time
broadly : change of velocity

Examples of acceleration in a Sentence

The car delivers quick acceleration. There has been some acceleration in economic growth. There has been an acceleration in economic growth.
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.
That is enough acceleration to make merging onto a freeway feel less like joining traffic and more like issuing a challenge to it. — New Atlas, 22 Aug. 2026 Passing and hard acceleration require some patience, especially with passengers aboard. — Josh Max, Forbes.com, 21 Aug. 2026 Instead, smoother acceleration, less frequent hard launches, and avoiding unnecessary cycles of heavy acceleration and braking could help reduce stress on one of the vehicle’s most expensive components. — Kaif Shaikh, Interesting Engineering, 20 Aug. 2026 To be eligible, incubators and accelerators had to be physically located in the United States, offer at least one incubation or acceleration program, and have been in operation since at least 2022. — Time Staff, Time, 18 Aug. 2026 See All Example Sentences for acceleration

Word History

Etymology

borrowed from Anglo-French & Latin; Anglo-French acceleratiun, borrowed from Latin accelerātiōn-, accelerātiō, from accelerāre "to accelerate" + -tiōn-, -tiō, suffix of action nouns

First Known Use

15th century, in the meaning defined at sense 1a

Time Traveler
The first known use of acceleration was in the 15th century

Phrases Containing acceleration

Rhymes for acceleration

See All Rhymes for acceleration

Browse Nearby Words

accelerating
acceleration
acceleration coefficient
See all Nearby Words

Cite this Entry

“Acceleration.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acceleration. Accessed 1 Sep. 2026.

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Kids Definition

acceleration

noun
ac·​cel·​er·​a·​tion ik-ˌsel-ə-ˈrā-shən How to pronounce acceleration (audio)
ak-
1
: the act or process of accelerating : the state of being accelerated
2
: the rate of change of velocity with respect to time
also : change in velocity

Medical Definition

acceleration

noun
ac·​cel·​er·​a·​tion ik-ˌsel-ə-ˈrā-shən, (ˌ)ak- How to pronounce acceleration (audio)
1
: the act or process of accelerating : the state of being accelerated
2
: change of velocity
also : the rate of this change
3
: advancement in mental growth or achievement beyond the average for one's age

More from Merriam-Webster on acceleration

Thesaurus: All synonyms and antonyms for acceleration

Britannica.com: Encyclopedia article about acceleration

Last Updated: - Updated example sentences
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