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

To keep things on the steady, the front and rear air suspension has been tuned to limit weight transfer—squat—during acceleration, the company says.

From The Wall Street Journal • Apr. 4, 2026

“The payments industry is changing faster than ever, driven by new technologies, evolving regulations, an increasingly competitive landscape, and the rapid acceleration of AI that is reshaping commerce daily,” Lores said in a February statement.

From Los Angeles Times • Apr. 3, 2026

This marks an acceleration from 48% growth in the fourth quarter of 2025 and is well above the Street’s call for 50% growth.

From Barron's • Apr. 2, 2026

"He has very good acceleration and technique. The boy will give us joy."

From BBC • Mar. 27, 2026

This acceleration, which characterizes the force of gravity holding us to the Earth’s surface, is called 1 g, g for Earth gravity.

From "Cosmos" by Carl Sagan