speed

Speed most often describes acceleration or a high rate of motion. When something picks up too much speed, it can run off course, like a kid on a bike zooming uncontrollably down a steep hill.

Speed can be a noun or verb. As a noun, it's an indicator of pace, as in the speed of a car. As a noun, it's also a drug that keeps you awake, very awake. As a verb, it means to “move along quickly,” like how you speed around on your bike. A fun fact: while speed refers to the distance traveled by an object during a specific amount of time, velocity describes that distance, but in a specified direction.

Primary Meanings of speed

1.
 nv
a rate (usually rapid) at which something happens
move fast
2.
 n
the ratio of the focal length to the diameter of a (camera) lens system
3.
 n
a central nervous system stimulant that increases energy and decreases appetite; used to treat narcolepsy and some forms of depression
Full Definitions of speed
1

n a rate (usually rapid) at which something happens

“the project advanced with gratifying speed”
Synonyms:
fastness, swiftness
Types:
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haste, hastiness, hurriedness, hurry, precipitation
overly eager speed (and possible carelessness)
execution speed
(computer science) the speed with which a computational device can execute instructions; measured in MIPS
graduality, gradualness
the quality of being gradual or of coming about by gradual stages
abruptness, precipitance, precipitancy, precipitateness, precipitousness, suddenness
the quality of happening with headlong haste or without warning
Type of:
pace, rate
the relative speed of progress or change

n distance travelled per unit time

Synonyms:
velocity
Types:
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angular velocity
(physics) the rate of change of the angular position of a rotating body; usually expressed in radians per second or radians per minute
airspeed
the speed of an aircraft relative to the air in which it is flying
escape velocity
the minimum velocity needed to escape a gravitational field
groundspeed
the speed of an aircraft relative to the ground
hypervelocity
excessive velocity
muzzle velocity
the velocity of a projectile as it leaves the muzzle of a gun
peculiar velocity
velocity with respect to the local standard of rest
radial velocity
velocity along the line of sight toward or away from the observer
c, light speed, speed of light
the speed at which light travels in a vacuum; the constancy and universality of the speed of light is recognized by defining it to be exactly 299,792,458 meters per second
steerageway
(nautical) the minimum rate of motion needed for a vessel to be maneuvered
terminal velocity
the constant maximum velocity reached by a body falling through the atmosphere under the attraction of gravity
Type of:
rate
a magnitude or frequency relative to a time unit

n changing location rapidly

Synonyms:
hurrying, speeding
Types:
acceleration, quickening, speedup
the act of accelerating; increasing the speed
deceleration
the act of decelerating; decreasing the speed
scud, scudding
the act of moving along swiftly (as before a gale)
Type of:
motion, move, movement
the act of changing location from one place to another

v move fast

Synonyms:
belt along, bucket along, cannonball along, hasten, hie, hotfoot, pelt along, race, rush, rush along, step on it
Antonyms:
dawdle, linger
take one's time; proceed slowly
Types:
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barge, push forward, thrust ahead
push one's way
buck, charge, shoot, shoot down, tear
move quickly and violently
dart, dash, flash, scoot, scud, shoot
run or move very quickly or hastily
plunge
dash violently or with great speed or impetuosity
rip
move precipitously or violently
Type of:
go, locomote, move, travel
change location; move, travel, or proceed, also metaphorically

v move faster

Synonyms:
accelerate, quicken, speed up
Antonyms:
decelerate, retard, slow, slow down, slow up
lose velocity; move more slowly
Types:
brisk, brisk up, brisken
become brisk
Type of:
deepen, intensify
become more intense

v move very fast

“The runner zipped past us at breakneck speed”
Synonyms:
hurry, travel rapidly, zip
Types:
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dart, fleet, flit, flutter
move along rapidly and lightly; skim or dart
run
move fast by using one's feet, with one foot off the ground at any given time
whizz, whizz along, zoom, zoom along
move along very quickly
butterfly
flutter like a butterfly
clip, jog, trot
run at a moderately swift pace
scamper, scurry, scuttle, skitter
to move about or proceed hurriedly
romp
run easily and fairly fast
run bases
run around the bases, in baseball
streak
run naked in a public place
run
run with the ball; in such sports as football
outrun
run faster than
jog
run for exercise
sprint
run very fast, usually for a short distance
lope
run easily
rush
run with the ball, in football
hare
run quickly, like a hare
Type of:
go, locomote, move, travel
change location; move, travel, or proceed, also metaphorically

v travel at an excessive or illegal velocity

“I got a ticket for speeding”
Type of:
go, locomote, move, travel
change location; move, travel, or proceed, also metaphorically

v cause to move faster

Synonyms:
accelerate, speed up
Antonyms:
decelerate, slow down
reduce the speed of
Type of:
alter, change, modify
cause to change; make different; cause a transformation
2

n the ratio of the focal length to the diameter of a (camera) lens system

Synonyms:
f number, focal ratio, stop number
Type of:
ratio
the relative magnitudes of two quantities (usually expressed as a quotient)
3

n a central nervous system stimulant that increases energy and decreases appetite; used to treat narcolepsy and some forms of depression

Types:
amphetamine sulfate, amphetamine sulphate
a sulfate derivative of amphetamine that is used as a stimulant for the central nervous system
Benzedrine, bennie
a form of amphetamine
Dexedrine, dextroamphetamine sulphate
an isomer of amphetamine (trade name Dexedrine) used as a central nervous system stimulant
Type of:
drug of abuse, street drug
a drug that is taken for nonmedicinal reasons (usually for mind-altering effects); drug abuse can lead to physical and mental damage and (with some substances) dependence and addiction
excitant, stimulant, stimulant drug
a drug that temporarily quickens some vital process

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