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English definition of “speed”

speed

noun (RATE OF MOVEMENT)    /spiːd/
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 gear nounGrammar:MeasurementsSee moreGrammar:Area: length, width, depth and heightWe use the nouns length, width, depth and height and the adjectives long, wide, deep and high to talk about area and size:See moreGrammar:Weight and volumeWe use the verb weigh to measure weight:See moreGrammar:Frequency, speed, timeWe use many different expressions to describe frequency, speed and time. Here are some of them:See more
(Definition of speed noun (RATE OF MOVEMENT) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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