from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A device, especially the gas pedal of a motor vehicle, for increasing speed.
  • noun Chemistry A substance that increases the speed of a reaction.
  • noun Physics A particle accelerator.

from The Century Dictionary.

  • noun One who or that which accelerates; a hastener.
  • noun A device in a motor-car by which the operator may render inoperative the speed governor of the motor. If the governor is of the centrifugal type, as the speed increases the balls or weights fly outward against the action of a spring. The accelerator increases the tension of the spring or draws the balls inward directly, so that the governor ceases to act to close the throttle or regulate speed as the motor increases its number of revolutions above the limit set by the normal tension of the springs.

from the GNU version of the Collaborative International Dictionary of English.

  • noun One who, or that which, accelerates. Also as an adj..

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun One who, or that which, accelerates.
  • noun A device for causing acceleration.
  • noun chemistry A substance which speeds up chemical reactions.
  • noun vehicles An accelerator pedal.
  • noun photography A chemical that reduces development time.
  • noun physics A device that accelerates charged subatomic particles.
  • noun physiology, medicine A muscle or nerve that speed the performance of an action.
  • noun computing accelerator key

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a valve that regulates the supply of fuel to the engine
  • noun (chemistry) a substance that initiates or accelerates a chemical reaction without itself being affected
  • noun a scientific instrument that increases the kinetic energy of charged particles
  • noun a pedal that controls the throttle valve


Sorry, no etymologies found.


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  • Startup accelerators support early-stage, growth-driven companies through education, mentorship, and financing. Startups enter accelerators for a fixed-period of time, and as part of a cohort of companies. The accelerator experience is a process of intense, rapid, and immersive education aimed at accelerating the life cycle of young innovative companies, compressing years’ worth of learning-by-doing into just a few months.

    Susan Cohen of the University of Richmond and Yael Hochberg of Rice University highlight the four distinct factors that make accelerators unique: they are fixed-term, cohort-based, and mentorship-driven, and they culminate in a graduation or “demo day.” None of the other previously mentioned early-stage institutions — incubators, angel investors, or seed-stage venture capitalists — have these collective elements. Accelerators may share with these others the goal of cultivating early-stage startups, but it is clear that they are different, with distinctly different business models and incentive structures.

    Ian Hathaway, What Startup Accelerators Really Do, Harvard Business Review, March 1, 2016.

    What do accelerators do? Broadly speaking, they help ventures define and build their initial products, identify promising customer segments, and secure resources, including capital and employees. More specifically, accelerator programs are limited-duration programs—lasting roughly three months—that help cohorts of ventures with the new venture process. They usually provide a small amount of seed capital, plus working space. They also offer a plethora of networking, educational and mentorship opportunities, with both peer ventures and mentors, who might be successful entrepreneurs, program graduates, venture capitalists, angel investors, or even corporate executives. Finally, most programs end with a grand event, usually a “demo day” where ventures pitch to a large audience of qualified investors (Cohen 2013).

    . . . We thus define the Seed Accelerator as follows:

    A fixed-term, cohort-based program, including mentorship and educational components, that culminates in a public pitch event or demo-day.
    Susan G. Cohen & Yael V. Hochberg, Accelerating Startups: The Seed Accelerator Phenomenon, March 2014.

    March 2, 2016