speed

[ speed ]

/ spid /

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See synonyms for: speed / sped / speeding on Thesaurus.com

noun

rapidity in moving, going, traveling, proceeding, or performing; swiftness; celerity: the speed of light;the speed of sound.

relative rapidity in moving, going, etc.; rate of motion or progress: full speed ahead.

full, maximum, or optimum rate of motion: The car gets to speed in just nine seconds.

Automotive. a transmission gear ratio.

Photography.

Also called film speed . the sensitivity of a film or paper to light, measured by an ASA or DIN index, which assigns low numbers to slow film and higher numbers to faster film.
Also called shutter speed . the length of time a shutter is opened to expose the film or digital sensor inside the camera to light.
the largest opening at which a lens can be used.

Slang. a stimulating drug, as caffeine, ephedrine, or especially methamphetamine or amphetamine.

Informal. a person or thing that is compatible with or typical of one's ability, personality, desires, etc.: My speed is writing postcards on the porch while everyone else is tearing around the tennis court.

Archaic. success or prosperity.

verb (used with object), sped

[sped] /spɛd/ or speed·ed, speed·ing.

to promote the success of (an affair, undertaking, etc.); further, forward, or expedite.

to direct (the steps, course, way, etc.) with speed.

to increase the rate of speed of (usually followed by up): to speed up industrial production.

to bring to a particular speed, as a machine.

to cause to move, go, or proceed with speed.

to expedite the going of: to speed the parting guest.

Archaic. to cause to succeed or prosper.

verb (used without object), sped

[sped] /spɛd/ or speed·ed, speed·ing.

to move, go, pass, or proceed with speed or rapidity.

to drive a vehicle at a rate that exceeds the legally established maximum: He was arrested for speeding.

to increase the rate of speed or progress (usually followed by up).

to get on or fare in a specified or particular manner.

Archaic. to succeed or prosper.

OTHER WORDS FOR speed

1, 2 fleetness, alacrity, dispatch, expedition; hurry.

9 advance, facilitate, favor.

11 accelerate.

See synonyms for speed on Thesaurus.com

OPPOSITES FOR speed

1 slowness.

See antonyms for speed on Thesaurus.com

QUIZ

THINGAMABOB OR THINGUMMY: CAN YOU DISTINGUISH BETWEEN THE US AND UK TERMS IN THIS QUIZ?

Do you know the difference between everyday US and UK terminology? Test yourself with this quiz on words that differ across the Atlantic.

Question 1 of 7

In the UK, COTTON CANDY is more commonly known as…

candystring

candyfloss

candypuff

TAKE THE QUIZ TO FIND OUT

Idioms about speed

at full / top speed,

at the greatest speed possible: We drove down the highway at full speed.
to the maximum of one's capabilities; with great rapidity: He worked at full speed.

up to speed,

operating at full or optimum speed.
functioning or producing at an expected, acceptable, or competitive level; up to par: a new firm not yet up to speed.

Origin of speed

First recorded 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”; (verb) Middle English speden “to succeed, prosper, go with speed,” Old English spēdan “to succeed, prosper”; cognate with Old Saxon spōdian, Old High German spuoten

synonym study for speed

1, 2. 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. 16. See rush¹.

OTHER WORDS FROM speed

speedful, adjectivespeed·ful·ly, adverbspeed·ful·ness, nounspeed·ing·ly, adverb

speed·ing·ness, nounspeedless, adjectivemul·ti·speed, adjectiveoutspeed, verb (used with object), out·sped or out·speed·ed, out·speed·ing.o·ver·speed, verb, o·ver·sped or o·ver·speed·ed, o·ver·speed·ing.

Words nearby speed

speech synthesis, speech therapy, speech-to-text, speechway, speechwriter, speed, speedball, speedboat, speedboating, speed brake, speed bump

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use speed in a sentence

Since then, total hours worked have rebounded at exactly the same speed.
Despite wildly different approaches, the US and UK are seeing identical declines in hours worked|Dan Kopf|September 17, 2020|Quartz
The discovery of this phenomenon, which theorists called universality, was as bizarre as finding that elephants and egrets move at precisely the same top speed.
How Mathematical ‘Hocus-Pocus’ Saved Particle Physics|Charlie Wood|September 17, 2020|Quanta Magazine
Added to which, a page that’s been properly optimized for speed might not need AMP for those speed gains, as well.
Google ranking factors to change search in 2021: Core Web Vitals, E-A-T, or AMP?|Aleh Barysevich|September 16, 2020|Search Engine Watch
You can coach sharpness within speeds, so that means how you start, how you push off and how you maintain your sprint speed by the technique that you use.
A Canadian Teenager Is One Of The Fastest Soccer Players In The World|Julian McKenzie|September 16, 2020|FiveThirtyEight

As the next flare runs into the protons released by the previous flare, it would accelerate protons and electrons in the same direction at the same speeds.
Neutrinos could reveal how fast radio bursts are launched|Lisa Grossman|September 16, 2020|Science News
Term limits could be a prescription to speed change along.
The Unbearable Whiteness of Congress|Dean Obeidallah|January 8, 2015|DAILY BEAST
He felt his body grow limp (like one of those high-speed films of a flower wilting).
Powerful Congressman Writes About ‘Fleshy Breasts’|Asawin Suebsaeng|January 7, 2015|DAILY BEAST
The jet engine instantly brought two advances over propellers: it doubled the speed and it was far more reliable.
Flight 8501 Poses Question: Are Modern Jets Too Automated to Fly?|Clive Irving|January 4, 2015|DAILY BEAST
One report has the AirAsia Airbus flying at a speed very close to what would trigger a low speed stall.
Did Bad Weather Bring Down AirAsia 8501?|Clive Irving|December 29, 2014|DAILY BEAST
Authorities blame anarchists protesting a proposed high-speed rail line called TAV that will link Turin and Lyon, France.
Italy’s Terror on the Tracks|Barbie Latza Nadeau|December 28, 2014|DAILY BEAST
Really, he had made astonishing speed for one who had tunnelled his way underp.
The Tale of Grandfather Mole|Arthur Scott Bailey
A long stretch of smooth ice followed, over which he glided with ever-increasing speed.
The Giant of the North|R.M. Ballantyne
Never again would he sit behind that wheel rejoicing in the insolence of speed.
The Joyous Adventures of Aristide Pujol|William J. Locke
In fact, his appearance was so formidable that Davy did not pause for a second look, but started off at the top of his speed.
Davy and The Goblin|Charles E. Carryl
And the girl, scarce believing her good fortune, departed with a speed that bordered on the ludicrous.
St. Martin's Summer|Rafael Sabatini

British Dictionary definitions for speed

speed

/ (spiːd) /

noun

the act or quality of acting or moving fast; rapidity

the rate at which something moves, is done, or acts

physics a scalar measure of the rate of movement of a body expressed either as the distance travelled divided by the time taken (average speed) or the rate of change of position with respect to time at a particular point (instantaneous speed). It is measured in metres per second, miles per hour, etc

a rate of rotation, usually expressed in revolutions per unit time

a gear ratio in a motor vehicle, bicycle, etc
(in combination)a three-speed gear

photog a numerical expression of the sensitivity to light of a particular type of film, paper, or plateSee also ISO rating

photog a measure of the ability of a lens to pass light from an object to the image position, determined by the aperture and also the transmitting power of the lens. It increases as the f-number is decreased and vice versa

a slang word for amphetamine

archaic prosperity or success

at speed quickly

up to speed

operating at an acceptable or competitive level
in possession of all the relevant or necessary information

verb speeds, speeding, sped or speeded

to move or go or cause to move or go quickly

(intr) to drive (a motor vehicle) at a high speed, esp above legal limits

(tr) to help further the success or completion of

(intr) slang to take or be under the influence of amphetamines

(intr) to operate or run at a high speed

archaic

(intr) to prosper or succeed
(tr) to wish success to

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

speed

[ spēd ]

The ratio of the distance traveled by an object (regardless of its direction) to the time required to travel that distance. Compare velocity.

Other Idioms and Phrases with speed

speed

In addition to the idiom beginning with speed

speed up

also see:

full speed ahead
up to par (speed)

speed

OTHER WORDS FOR speed

OPPOSITES FOR speed

Idioms about speed

Origin of speed

synonym study for speed

OTHER WORDS FROM speed

Words nearby speed

Words related to speed

How to use speed in a sentence

British Dictionary definitions for speed

Derived forms of speed

Word Origin for speed

Scientific definitions for speed

Other Idioms and Phrases with speed