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1

fast

play
adjective \ˈfast\

Simple Definition of fast

  • : moving or able to move quickly

  • : happening quickly : taking a short amount of time

  • : operating quickly

Source: Merriam-Webster's Learner's Dictionary

Full Definition of fast

  1. 1 a :  firmly fixed <roots fast in the ground> b :  tightly shut <the drawers were fast> c :  adhering firmly 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. 2 :  firmly loyal <became fast friends>

  3. 3 a :  characterized by quick motion, operation, or effect: (1) :  moving or able to move rapidly :  swift (2) :  taking a comparatively short time (3) :  imparting quickness of motion <a fast bowler> (4) :  accomplished quickly (5) :  agile of mind; especially :  quick to learn <a class for fast students> b :  conducive to rapidity of play or action c (1) of a timepiece or weighing device :  indicating in advance of what is correct (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. 4 a :  securely attached <a rope fast to the wharf> b :  tenacious <a fast hold on her purse>

  5. 5 a archaic :  sound asleep b of sleep :  not easily disturbed

  6. 6 :  not fading or changing color readily

  7. 7 a :  wild <a pretty fast crowd> b :  sexually promiscuous

  8. 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


First Known Use: before 12th century

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

Simple Definition of fast

  • : 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of fast

  1. 1 :  in a firm or fixed manner <stuck fast>

  2. 2 :  in a sound manner :  deeply <fast asleep>

  3. 3 a :  in a rapid manner :  quickly b :  in quick succession

  4. 4 :  in a reckless or dissipated manner

  5. 5 :  ahead of a correct time or schedule

  6. 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!



Before 12th Century

First Known Use of fast

before 12th century


3

fast

verb

Simple Definition of fast

  • : to eat no food for a period of time

Source: Merriam-Webster's Learner's Dictionary

Full Definition of fast

  1. intransitive verb
  2. 1 :  to abstain from food

  3. 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


First Known Use: before 12th century


4

fast

noun

Definition of fast

  1. 1 :  the practice of fasting

  2. 2 :  a time of fasting



Before 12th Century

First Known Use of fast

before 12th century


5

fast

noun

Definition of fast

  1. :  something that fastens (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


First Known Use: 15th century

Rhymes with fast



FAST Defined for Kids

1

fast

play
adjective \ˈfast\

Definition of fast for Students

faster

fastest

  1. 1 :  moving, operating, or acting quickly <a fast train> <a fast thinker>

  2. 2 :  taking a short time <a fast trip>

  3. 3 :  indicating ahead of the correct time <The clock is fast.>

  4. 4 :  firmly placed <The plant's roots were fast in the ground.>

  5. 5 :  not likely to fade <fast colors>

  6. 6 :  totally loyal <fast friends>



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

play
adverb

Definition of fast for Students

faster

fastest

  1. 1 :  with great speed <Don't walk so fast!>

  2. 2 :  to the full extent :  sound <fast asleep>

  3. 3 :  in a firm or fixed way <The rear wheels were stuck fast in the mud.>




3

fast

play
verb

Definition of fast for Students

fasted

fasting

  1. 1 :  to go without eating

  2. 2 :  to eat in small amounts or only certain foods




4

fast

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noun

Definition of fast for Students

  1. 1 :  the act of going without food

  2. 2 :  a time when no food is eaten




Medical Dictionary

1

fast

play
adjective \ˈfast\

Medical Definition of fast

  1. 1:  firmly fixed

  2. 2a:  having a rapid effect <a fast medicine>b:  allowing for the rapid passage of a gas or liquid

  3. 3:  resistant to change (as from destructive action)—used chiefly of organisms and in combination with the agent resisted <acid-fast bacteria>




2

fast

verb

Medical Definition of fast

  1. 1:  to abstain from food

  2. 2:  to eat sparingly or abstain from some foods

  3. transitive verb

  4. :  to deny food to <the patient is fasted and given a mild hypnotic—Lancet>




3

fast

noun

Medical Definition of fast

  1. 1:  the practice of fasting

  2. 2:  a time of fasting




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