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noun \ˈspēd\

Simple Definition of speed

  • : the rate at which someone or something moves or travels

  • : the rate at which something happens or is done

  • : the quality of being quick

Source: Merriam-Webster's Learner's Dictionary

Full Definition of speed

  1. 1 archaic :  prosperity in an undertaking :  success

  2. 2a :  the act or state of moving swiftly :  swiftnessb :  rate of motion: as (1) :  velocity 1 (2) :  the magnitude of a velocity irrespective of direction c :  impetus

  3. 3 :  swiftness or rate of performance or action :  velocity 3a

  4. 4a :  the sensitivity of a photographic film, plate, or paper expressed numericallyb :  the light-gathering power of a lens or optical systemc :  the time during which a camera shutter is open

  5. 5 :  a transmission gear in automotive vehicles or bicycles —usually used in combination <a ten-speed bicycle>

  6. 6 :  someone or something that appeals to one's taste <just my speed>

  7. 7 :  methamphetamine; also :  a related stimulant drug and especially an amphetamine


play \ˈspēd-stər\ noun

at speed

chiefly British

  1. :  fast, rapidly

up to speed

  1. :  operating at full effectiveness or potential

Examples of speed in a sentence

  1. This instrument measures wind speed.

  2. The machine was operating at high speed.

  3. traveling at nearly the speed of light

  4. Under the right conditions the car can reach speeds over 200 miles an hour.

  5. The vehicle maintained a speed of 40 miles per hour.

  6. The work was done with remarkable speed.

  7. This computer works at a much faster processing speed than my old one.

  8. The machine chops up tree branches and leaves with speed and ease.

Origin and Etymology of speed

Middle English spede, from Old English spēd; akin to Old High German spuot prosperity, speed, Old English spōwan to succeed, Latin spes hope, Lithuanian spėti to be in time

First Known Use: before 12th century

Synonym Discussion of speed

haste, hurry, speed, expedition, dispatch mean quickness in movement or action. haste applies to personal action and implies urgency and precipitancy and often rashness <marry in haste>. hurry often has a strong suggestion of agitated bustle or confusion <in the hurry of departure she forgot her toothbrush>. speed suggests swift efficiency in movement or action <exercises to increase your reading speed>. expedition and dispatch both imply speed and efficiency in handling affairs but expedition stresses ease or efficiency of performance and dispatch stresses promptness in concluding matters <the case came to trial with expedition> <paid bills with dispatch>.




Simple Definition of speed

  • : to move fast

  • : to move (someone or something) somewhere very quickly

  • : to drive faster than the legal speed limit

Source: Merriam-Webster's Learner's Dictionary

Full Definition of speed


play \ˈsped\ or



  1. intransitive verb
  2. 1a archaic :  to prosper in an undertakingb archaic :  get along, fare

  3. 2a :  to make haste <sped to her bedside>b :  to go or drive at excessive or illegal speed

  4. 3 :  to move, work, or take place faster :  accelerate <the heart speeds up>

  5. transitive verb
  6. 1a archaic :  to cause or help to prosper :  aidb :  to further the success of

  7. 2a :  to cause to move quickly :  hastenb :  to wish Godspeed toc :  to increase the speed of :  accelerate

  8. 3 :  to send out <speed an arrow>



Examples of speed in a sentence

  1. A group of kids sped past us on their bikes.

  2. They jumped in the car and sped away.

  3. A car was speeding down the street.

  4. An ambulance sped her to the hospital.

  5. I got pulled over twice last month because I was speeding on the highway.

Before 12th Century

First Known Use of speed

before 12th century

SPEED Defined for Kids



noun \ˈspēd\

Definition of speed for Students

  1. 1 :  quickness in movement or action

  2. 2 :  rate of moving or doing <a speed of 100 miles an hour>




Definition of speed for Students


\ˈsped\ or



  1. 1 :  to move or cause to move fast :  hurry

  2. 2 :  to go or drive at too high a rate of movement <I got a ticket for speeding.>

  3. 3 :  to increase the rate of an action or movement <How can we speed this process?>

speed up

  1. :  to move more quickly

Medical Dictionary


noun \ˈspēd\

Medical Definition of speed

  1. :  methamphetamine; also :  a related stimulant drug and especially an amphetamine

Seen and Heard

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to permeate or influence as if by dyeing

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