Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “speed”

speed

noun uk   /spiːd/ us  

speed noun (RATE OF MOVEMENT)

B1 [C or U] how fast something moves: He was travelling at a speed of 90 mph. The car has a top speed of 155 miles per hour. You should lower/reduce your speed as you approach a junction. On a clear, straight road you can gather/pick up speed. He came off the road while driving his car round a bend at high/breakneck speed (= very fast). There are speed restrictions (= controls on how fast traffic is allowed to move) on this part of the road. an electric drill with two speeds (= rates at which it turns)Speed of motion B2 [U] very fast movement: I get a real thrill from speed. He put on a sudden burst of speed. Both cars were travelling at speed (= very fast) when the accident happened.Speed of motion [U] how fast something happens: We were surprised at the speed of the response to our enquiry. It was the speed at which it all happened that shocked me. She got through her work with speed (= quickly) and efficiency.Hurrying and doing things quicklyBusy and activeFast and rapidShort in time the speed of light/sound the rate at which light or sound travels: The speed of light is 300 million metres per second. These planes travel at twice the speed of sound.Speed of motionThe engine and engine partsEngines and motors [C] a gear noun: a bicycle with ten speeds a ten-speed bicycleBicyclesThe engine and engine partsEngines and motors [C] the rate at which a photographic film absorbs or reacts to light: What speed film do I need for taking photographs indoors?Photography shutter speed the length of time for which part of a camera is open to allow light to reach the film when a photograph is being taken: a high/low shutter speedPhotography

speed noun (DRUG)

[U] slang for amphetamine (= a drug that makes the mind or body more active): She was on speed at the time.Specific types of drugDrugs - general wordsSpecific medicines and drugs

speed

verb [I or T, usually + adv/prep] uk   /spiːd/ (sped or speeded, sped or speeded) us  
to (cause to) move, go, or happen fast: The train sped along at over 120 miles per hour. The actress then sped away/off in a waiting car. We sped down the ski slopes. This year is speeding by/past. Ambulances sped the injured people (= moved them quickly) away from the scene. The best thing you can do to speed your recovery (= make it quicker) is to rest.Increasing and decreasing speed of motion be speeding to be driving faster than you are legally allowed to do: He was caught speeding.Driving and operating road vehiclesCrime - general words
Phrasal verbs
(Definition of speed from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of speed?
Add Cambridge dictionaries to your browser to your website

Definitions of “speed” in other dictionaries

Word of the Day

workmanship

the skill with which something was made or done

Word of the Day

Blog

Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More