1

fast

play
adjective \ ˈfast \

Definition of fast

1 a :firmly fixed
  • roots fast in the ground
b :tightly shut
  • the drawers were fast
c :adhering firmly
  • The boards were fast a few hours after being glued together.
d :not easily freed :stuck
  • a ball fast in the mouth of the cannon
e :stable
  • movable items were made fast to the deck
2 :firmly loyal
  • became fast friends
3 a :characterized by quick motion, operation, or effect:
(1) :moving or able to move rapidly :swift
  • a fast horse
(2) :taking a comparatively short time
  • a fast race
(3) :imparting quickness of motion
  • a fast bowler
(4) :accomplished quickly
  • fast work
(5) :agile of mind; especially :quick to learn
  • a class for fast students
b :conducive to rapidity of play or action
  • a fast track
c (1) of a timepiece or weighing device :indicating in advance of what is correct
  • Your clock is two minutes fast.
(2) :according to or being daylight saving time
d :contributing to a shortening of exposure time
  • fast film
e :acquired with unusually little effort and often by shady or dishonest methods
  • had a keen eye for a fast buck
  • —R. A. Keith
4 a :securely attached
  • a rope fast to the wharf
b :tenacious
  • a fast hold on her purse
5 a archaic :sound asleep
b of sleep :not easily disturbed
  • fell into a fast sleep
6 :not fading or changing color readily
  • fast colors
7 a :actively seeking excitement and pleasure :wild
  • a pretty fast crowd
b :sexually promiscuous
8 :resistant to change (as from destructive action or fading)
  • fast dyes
often used in combination
  • sunfast
  • acid-fast bacteria

Examples of fast in a Sentence

  1. She's a very fast runner.

  2. We're off to a fast start.

  3. We're now experiencing a faster rate of inflation.

  4. We took the faster route.

Origin and Etymology of fast

Middle English, from Old English fæst; akin to Old High German festi firm, Old Norse fastr, Armenian hast

Synonym Discussion of fast

fast, rapid, swift, fleet, quick, speedy, hasty, expeditious mean moving, proceeding, or acting with celerity. fast and rapid are very close in meaning, but fast applies particularly to the thing that moves
    • fast horses
and rapid to the movement itself.
    • rapid current
swift suggests great rapidity coupled with ease of movement.
    • returned the ball with one swift stroke
fleet adds the implication of lightness and nimbleness.
    • fleet runners
quick suggests promptness and the taking of little time.
    • a quick wit
speedy implies quickness of successful accomplishment
    • speedy delivery of mail
and may also suggest unusual velocity. hasty suggests hurry and precipitousness and often connotes carelessness.
    • a hasty inspection
expeditious suggests efficiency together with rapidity of accomplishment.
    • the expeditious handling of an order

2

fast

adverb

Definition of fast

1 :in a firm or fixed manner
  • stuck fast
2 :in a sound manner :deeply
  • fast asleep
3 a :in a rapid manner :quickly
b :in quick succession
4 :in a reckless or dissipated manner
5 :ahead of a correct time or schedule
6 archaic :close, near

Examples of fast in a Sentence

  1. The boss expects this to be done this afternoon, so you'd better work fast.

  2. He ran as fast as he could.

  3. This is fast becoming a national problem.

  4. You need to act fast to take advantage of this offer.

  5. I don't know what caused the accident. It all happened so fast.

  6. She's a woman who can think fast in a crisis.

  7. He's going to have to talk fast to get himself out of this mess.

  8. The window was stuck fast.

  9. She held fast to her belief in justice.

  10. We must stand fast and not surrender!

Origin and Etymology of fast

see 1fast

fast Synonyms

Synonyms
apace, briskly, chop-chop, double-quick, fleetly, full tilt, hastily, hell-for-leather, hot, lickety-split, posthaste, presto, pronto, quick, quickly, rapidly, snappily, soon, speedily, swift, swiftly, a mile a minute, at full throttle, at full tilt, by leaps and bounds, in a hurry, in short order, like a shot, like gangbusters, like wildfire
Antonyms
slow, slowly
Related Words
immediately, promptly, readily; impetuously, impulsively, rashly, recklessly; abruptly, suddenly; energetically, vigorously
Near Antonyms
laggardly, lingeringly, ploddingly, sluggishly; deliberately, leisurely; belatedly, delinquently, tardily

3

fast

verb

Definition of fast

intransitive verb
1 :to abstain from food
2 :to eat sparingly or abstain from some foods

Examples of fast in a Sentence

  1. She always fasts on Yom Kippur.

  2. Patients must fast for six hours before having the procedure.

Origin and Etymology of fast

Middle English, from Old English fæstan


4

fast

noun

Definition of fast

1 :the practice of fasting
2 :a time of fasting

Origin and Etymology of fast

see 3fast


5

fast

noun

Definition of fast

:something that fastens (such as a mooring line) or holds a fastening

Origin and Etymology of fast

alteration of Middle English fest, from Old Norse festr rope, mooring cable, from fastr firm



FAST Defined for English Language Learners

fast

play
adjective

Definition of fast for English Language Learners

  • : moving or able to move quickly

  • : happening quickly : taking a short amount of time

  • : operating quickly


fast

adverb

Definition of fast for English Language Learners

  • : with great speed : in a very short time : very quickly

  • : in a quick and intelligent way

  • : quickly and in a way that is meant to deceive or persuade someone


fast

verb

Definition of fast for English Language Learners

  • : to eat no food for a period of time


FAST Defined for Kids

1

fast

play
adjective \ ˈfast \

Definition of fast for Students

faster; fastest
1 :moving, operating, or acting quickly
  • a fast train
  • a fast thinker
2 :taking a short time
  • a fast trip
3 :indicating ahead of the correct time
  • The clock is fast.
4 :firmly placed
  • The plant's roots were fast in the ground.
5 :not likely to fade
  • fast colors
6 :totally loyal
  • fast friends

Synonym Discussion of fast

fast, rapid, and swift mean moving, proceeding, or acting with great speed. fast is used of the thing that moves.
    • He rode a fast horse.
rapid is used of the speedy movement itself.
    • The horse moved at a rapid pace.
swift suggests ease of movement along with great speed.
    • A swift horse can easily jump the fence.

Headscratcher for fast

Someone fast can move very quickly while something held fast is stuck in one place and can't move anywhere at all!


2

fast

adverb

Definition of fast for Students

faster; fastest
1 :with great speed
  • Don't walk so fast!
2 :to the full extent :sound
  • fast asleep
3 :in a firm or fixed way
  • The rear wheels were stuck fast in the mud.

3

fast

verb

Definition of fast for Students

fasted; fasting
1 :to go without eating
2 :to eat in small amounts or only certain foods

4

fast

noun

Definition of fast for Students

1 :the act of going without food
2 :a time when no food is eaten

Medical Dictionary

1

fast

play
adjective \ ˈfast \

medical Definition of fast

1 :firmly fixed
2 a :having a rapid effect
  • a fast medicine
b :allowing for the rapid passage of a gas or liquid
3 :resistant to change (as from destructive action) used chiefly of organisms and in combination with the agent resisted
  • acid-fast bacteria

2

fast

intransitive verb

medical Definition of fast

1 :to abstain from food
2 :to eat sparingly or abstain from some foods
transitive verb
:to deny food to
  • the patient is fasted and given a mild hypnotic
  • Lancet

3

fast

noun

medical Definition of fast

1 :the practice of fasting
2 :a time of fasting


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