[ speed ]
/ spid /


verb (used with object), sped or speed·ed, speed·ing.

verb (used without object), sped or speed·ed, speed·ing.



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Question 1 of 10

Idioms for speed

    at full/top speed,
    1. at the greatest speed possible: We drove down the highway at full speed.
    2. to the maximum of one's capabilities; with great rapidity: He worked at full speed.
    up to speed,
    1. operating at full or optimum speed.
    2. functioning or producing at an expected, acceptable, or competitive level; up to par: a new firm not yet up to speed.

Origin of speed

before 900; 1965–70 for def 6; (noun) Middle English spede good luck, prosperity, rapidity, Old English spēd; cognate with Dutch spoed, Old High German spōt; akin to Old English spōwan to prosper, succeed; (v.) Middle English speden to succeed, prosper, go with speed, Old English spēdan to succeed, prosper; cognate with Old Saxon spōdian, Old High German spuoten


1, 2 fleetness, alacrity, dispatch, expedition; hurry. Speed, velocity, quickness, rapidity, celerity, haste refer to swift or energetic movement or operation. Speed (originally prosperity or success) may apply to human or nonhuman activity and emphasizes the rate in time at which something travels or operates: the speed of light, of a lens, of an automobile, of thought. Velocity, a more learned or technical term, is sometimes interchangeable with speed : the velocity of light; it is commonly used to refer to high rates of speed, linear or circular: velocity of a projectile. Quickness, a native word, and rapidity, a synonym of Latin origin, suggest speed of movement or operation on a small or subordinate scale; quickness applies more to people ( quickness of mind, of perception, of bodily movement ), rapidity more to things, often in a technical or mechanical context: the rapidity of moving parts; a lens of great rapidity. Celerity, a somewhat literary synonym of Latin origin, refers usually to human movement or operation and emphasizes expedition, dispatch, or economy in an activity: the celerity of his response. Haste refers to the energetic activity of human beings under stress; it often suggests lack of opportunity for care or thought: to marry in haste; a report prepared in haste.
9 advance, favor.
11 accelerate.
16 See rush1.


Definition for speed up (2 of 2)

[ speed-uhp ]
/ ˈspidˌʌp /


an increasing of speed.
an imposed increase in the rate of production of a worker without a corresponding increase in the rate of pay.

Origin of speed-up

First recorded in 1920–25; noun use of verb phrase speed up
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

British Dictionary definitions for speed up (1 of 2)

speed up

verb (adverb)

to increase or cause to increase in speed or rate; accelerate

noun speed-up

an instance of this; acceleration

usage for speed up

The past tense and past participle of speed up is speeded up, not sped up

British Dictionary definitions for speed up (2 of 2)

/ (spiːd) /


verb speeds, speeding, sped or speeded

See also speed up

Derived forms of speed

speeder, noun

Word Origin for speed

Old English spēd (originally in the sense: success); related to spōwan to succeed, Latin spēs hope, Old Slavonic spěti to be lucky
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

Scientific definitions for speed up

[ spēd ]

The ratio of the distance traveled by an object (regardless of its direction) to the time required to travel that distance. Compare velocity.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Idioms and Phrases with speed up (1 of 2)

speed up

Accelerate, expedite, increase the rate, as in The car speeded up as it went downhill, or It's difficult to speed up production without new equipment. [Late 1800s]

Idioms and Phrases with speed up (2 of 2)


The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.