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Noun: speed  speed
  1. The rate of movement; distance travelled per unit time
    - velocity
  2. A rate (usually rapid) at which something happens
    "the project advanced with gratifying speed";
    - swiftness, fastness
  3. Changing location rapidly
    - speeding, hurrying
  4. The ratio of the focal length to the diameter of a (camera) lens system
    - focal ratio, f number, stop number
  5. [informal] A central nervous system stimulant that increases energy and decreases appetite; used to treat narcolepsy and some forms of depression
    - amphetamine, pep pill [informal], upper [informal]
Verb: speed (sped, also speeded)  speed
  1. Move or travel very quickly
    "He sped down the hall to receive his guests";
    - rush, hotfoot, hasten, hie [archaic], race, pelt along [informal], rush along, bucket along [informal], belt along [informal], step on it [informal], travel rapidly, hurry, zip [informal], zoom, zoom along, whizz [informal], whizz along [informal], bucket [informal], wing [informal], pelt [informal], barrel [informal], rocket [informal], belt [informal]
  2. Move faster
    "The car sped up";
    - accelerate, speed up, quicken
  3. Travel at an excessive or illegal velocity
    "I got a ticket for speeding"
  4. Cause to move faster
    "He sped up the car";
    - accelerate, speed up

Derived forms: speeding, sped, speeds, speeded

See also: fast, slow

Type of: alter, change, deepen, drug of abuse, excitant, go, intensify, locomote, modify, motion, move, movement, pace, rate, ratio, stimulant, stimulant drug, street drug, travel

Encyclopedia: Speed, North Carolina