| to spend time idly; loaf. |
| to chew (food) slowly and thoroughly. |
speed (spiːd) ![]() | |
| —n | |
| 1. | the act or quality of acting or moving fast; rapidity |
| 2. | the rate at which something moves, is done, or acts |
| 3. | 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 | |
| 4. | a rate of rotation, usually expressed in revolutions per unit time |
| 5. | a. a gear ratio in a motor vehicle, bicycle, etc |
| b. (in combination): a three-speed gear | |
| 6. | photog See also ISO rating a numerical expression of the sensitivity to light of a particular type of film, paper, or plate |
| 7. | 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 |
| 8. | a slang word for amphetamine |
| 9. | archaic prosperity or success |
| 10. | at speed quickly |
| 11. | up to speed |
| a. operating at an acceptable or competitive level | |
| b. in possession of all the relevant or necessary information | |
| —vb , speeds, speeding, sped, speeded | |
| 12. | to move or go or cause to move or go quickly |
| 13. | (intr) to drive (a motor vehicle) at a high speed, esp above legal limits |
| 14. | (tr) to help further the success or completion of |
| 15. | slang (intr) to take or be under the influence of amphetamines |
| 16. | (intr) to operate or run at a high speed |
| 17. | archaic |
| a. (intr) to prosper or succeed | |
| b. (tr) to wish success to | |
| [Old English spēd (originally in the sense: success); related to spōwan to succeed, Latin spēs hope, Old Slavonic spěti to be lucky] | |
| 'speeder | |
| —n | |
"[T]he ancient Greeks & Romans knew what speed was, & yet no-one supposes they called it speed, whence it follows that speedo- & speedometer are barbarisms." [Fowler]Speed bump is 1975; figurative sense is 1990s. Full speed is recorded from 1382. Speed reading first attested 1965. Speedball "mix of cocaine and morphine or heroin" is recorded from 1909.
| speed (spēd) Pronunciation Key
The ratio of the distance traveled by an object (regardless of its direction) to the time required to travel that distance. Compare velocity. |
speed definition
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speed
In addition to the idiom beginning with speed, also see full speed ahead; up to par (speed).
speed
in photography, any of those standards that indicate (1) the size of the lens opening, or aperture, (2) the duration of exposure, and (3) the sensitivity of the film to light.
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