Acceleration
ak-sel-uh-RAY-shun
/ækˌsɛləˈreɪʃən/
The rate at which the velocity of an object changes over time.
Acceleration can mean speeding up, slowing down (deceleration), or changing direction, as all these involve a change in velocity. It is also a vector quantity.
The story behind the word. "Acceleration" comes from the Latin "acceleratio," meaning "a hastening." This is derived from "accelerare," meaning "to hasten," which combines "ad-" (to) and "celer" (swift). So, the word literally means "to add swiftness," perfectly capturing its scientific meaning.
Word relationships
- quickening: A more general term for speeding up, less precise than "acceleration" in a scientific context.
- boost: Implies an increase in speed or power, but not necessarily a sustained rate of change.
- deceleration: A specific type of acceleration where velocity decreases.
- slowing: General term for reducing speed.
Commonly confused with
- Speed: Speed is how fast; acceleration is how quickly speed (or direction) changes.
Word family
- accelerate (verb): To increase speed or rate.
- accelerator (noun): A device for increasing speed.
Collocations
- constant acceleration
- linear acceleration
- angular acceleration
- gravitational acceleration
- rapid acceleration
Idioms & expressions
- pedal to the metal (implies rapid acceleration)
Example sentences
- "The sports car boasted impressive acceleration, going from 0 to 60 mph in under three seconds." Describing a car's performance.
- "Acceleration is directly proportional to the net force acting on an object and inversely proportional to its mass." From a physics textbook. (Newton's Second Law of Motion)
Memory hook
Imagine an ACCELERATOR pedal that makes your car go FASTER and FASTER. Pedal Acceleration
When not to use
Do not use "acceleration" to simply mean "speeding up" if the context requires precision about the rate of change or if the change is in direction only.
Fun facts
- The acceleration due to gravity on Earth's surface is approximately 9.8 m/s².
- Astronauts experience high G-force acceleration during rocket launches.
Explore more words
accelerate, decelerate, agility, Depreciation, Calculus, accretion
Take your vocabulary further with LangBlitz
Our English vocabulary app: FSRS spaced repetition, 5,000+ curated words across 119 topic groups, CEFR A1 to C2. Explore your mastery with the beautiful Vocabulary World feature.