acceleration
ak-sel-uh-RAY-shun
/əkˌseləˈreɪʃən/
The rate at which the speed or direction of an object changes over time.
In sprinting, it specifically refers to the phase where the runner is gaining speed from a stationary start.
The story behind the word. From the Latin 'ad' (to) and 'celerare' (hasten), from 'celer' (swift). It describes the process of adding more swiftness to an object.
Word relationships
- hastening: Hastening is more general; acceleration is a precise physical measurement.
- deceleration: Deceleration is the rate of slowing down.
Commonly confused with
- momentum: Momentum is the 'weight' of a moving object; acceleration is how fast it's getting faster.
Word family
- accelerate (verb): To begin to move more quickly.
- accelerator (noun): A device, typically a pedal, that controls the speed of a vehicle.
Collocations
- rapid acceleration
- constant acceleration
- acceleration phase
Example sentences
- "The sprinter's acceleration out of the blocks was so explosive that he gained a two-meter lead instantly." Sprinting
- "The car's acceleration from 0 to 60 mph is its most impressive feature." Automotive
Memory hook
Think of the 'Accelerator' pedal in a car—you press it to go faster. Acceleration = Adding speed.
When not to use
Don't confuse with 'velocity,' which is the speed itself, not the rate of change.
Fun facts
- Gravity on Earth causes an acceleration of 9.8 meters per second squared for falling objects.
Related words
Explore more words
accelerate, decelerate, agility, Depreciation, Calculus, accretion
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