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[ak-sel-uh-rey-ter] /ækˈsɛl əˌreɪ tər/
a person or thing that accelerates.
Automotive. a device, usually operated by the foot, for controlling the speed of an engine.
British. any two- or three-wheeled motor vehicle, as a motorcycle or motor scooter.
Photography. a chemical, usually an alkali, added to a developer to increase the rate of development.
Also called accelerant. Chemistry. any substance that increases the speed of a chemical change, as one that increases the rate of vulcanization of rubber or that hastens the setting of concrete, mortar, plaster, or the like.
Anatomy, Physiology. any muscle, nerve, or activating substance that quickens a movement.
Also called atom smasher, particle accelerator. Physics. an electrostatic or electromagnetic device, as a cyclotron, that produces high-energy particles and focuses them on a target.
Origin of accelerator
1605-15; 1930-35 for def 7; accelerate + -or2 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for accelerator
  • But an exploding star can be expected to have produced also some more energetic particles than a mere human-built accelerator.
  • To produce these high-energy photons, they used a device called a linear accelerator.
  • It can only be done by bouncing photons off a high energy beam of electrons circulating in a particle accelerator.
  • In some instances, it's been reported, drivers have mistakenly continued to press the accelerator for up to twelve seconds.
  • Then, as traffic moves, the vehicle accelerates with a simple tap on the accelerator.
  • Don't even think about whining about how the physics students should pay the full cost of the accelerator.
  • He worked in games for decades before deciding to head up the accelerator.
  • It's the longest-lived startup accelerator in the country.
  • In one case both the brake and accelerator pedals were depressed.
  • Government policy thus has one foot on the accelerator of deficit spending and the other foot on the brake of interest rates.
British Dictionary definitions for accelerator


a device for increasing speed, esp a pedal for controlling the fuel intake in a motor vehicle; throttle
(physics) Also called (not in technical usage) atom smasher. a machine for increasing the kinetic energy of subatomic particles or atomic nuclei and focusing them on a target
(chem) a substance that increases the speed of a chemical reaction, esp one that increases the rate of vulcanization of rubber, the rate of development in photography, the rate of setting of synthetic resins, or the rate of setting of concrete; catalyst
(economics) (in an economy) the relationship between the rate of change in output or sales and the consequent change in the level of investment
(anatomy) a muscle or nerve that increases the rate of a function
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for accelerator

1610s, from Latin accelerator, agent noun from accelerare (see accelerate). Motor vehicle sense is from 1900.

Online Etymology Dictionary, © 2010 Douglas Harper
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accelerator in Medicine

accelerator ac·cel·er·a·tor (āk-sěl'ə-rā'tər)

  1. One that increases rapidity of action or function.

  2. A nerve, muscle, or substance that quickens movement or response.

  3. A catalyst.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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accelerator in Technology
Additional hardware to perform some function faster than is possible in software running on the normal CPU. Examples include graphics accelerators and floating-point accelerators.
The Free On-line Dictionary of Computing, © Denis Howe 2010
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