acceleration

American  

[ak-sel-uh-rey-shuhn, ik-] / ækˌsɛl əˈreɪ ʃən, ɪk- /

noun

1. the act of accelerating; increase of speed or velocity.

2. a change in velocity.

3. Mechanics. the time rate of change of velocity with respect to magnitude or direction; the derivative of velocity with respect to time.

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acceleration British  

/ ækˌsɛləˈreɪʃən /

noun

1. the act of accelerating or the state of being accelerated

2.  a.  the rate of increase of speed or the rate of change of velocity

3.  a.  the power to accelerate

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acceleration Scientific  

/ ăk-sĕl′ə-rā′shən /

1. The rate of change of the velocity of a moving body. An increase in the magnitude of the velocity of a moving body (an increase in speed) is called a positive acceleration; a decrease in speed is called a negative acceleration. Acceleration, like velocity, is a vector quantity, so any change in the direction of a moving body is also an acceleration. A moving body that follows a curved path, even when its speed remains constant, is undergoing acceleration.

2. See more at gravity relativity

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acceleration Cultural  

1. A change in the velocity of an object.

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Discover More

The most familiar kind of acceleration is a change in the speed of an object. An object that stays at the same speed but changes direction, however, is also being accelerated. (See force.)

Other Word Forms

• nonacceleration noun
• overacceleration noun
• reacceleration noun

Etymology

Origin of acceleration

First recorded in 1525–35, acceleration is from the Latin word accelerātiōn- (stem of accelerātiō ). See accelerate, -ion

Example Sentences

According to ISS, another eyebrow-raising element was that the vast majority of Zaslav’s estimated compensation — over 94% — was being derived by the automatic acceleration of stock vesting and the excise tax gross-up payment.

From Los Angeles Times • Apr. 9, 2026

“Progress will not be linear. There will be moments of acceleration and moments where we adjust course,” Jassy said.

From MarketWatch • Apr. 9, 2026

“We are seeing a clear acceleration in demand for high-performance AI data center capacity, with hyperscalers as aggressive as we have ever seen them,” Applied Digital CEO Wes Cummins said in the earnings release.

From Barron's • Apr. 8, 2026

Modern elevator advances give priority to smoother acceleration, energy efficiency and integration with autonomous robots.

From The Wall Street Journal • Apr. 2, 2026

All of the train’s braking and acceleration came in jerks and shuddering decelerations that threatened to throw them off their perches.

From "Ship Breaker" by Paolo Bacigalupi