fast

adjective
\ˈfast \

Definition of fast 

(Entry 1 of 5)

1a : 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

3a : 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

4a : securely attached a rope fast to the wharf

b : tenacious a fast hold on her purse

5a archaic : sound asleep

b of sleep : not easily disturbed fell into a fast sleep

6 : not fading or changing color readily fast colors

7a : 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 sunfastacid-fast bacteria

fast

adverb

Definition of fast (Entry 2 of 5)

1 : in a firm or fixed manner stuck fast

2 : in a sound manner : deeply fast asleep

3a : 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

fast

verb
fasted; fasting; fasts

Definition of fast (Entry 3 of 5)

intransitive verb

1 : to abstain from food

2 : to eat sparingly or abstain from some foods

fast

noun (1)

Definition of fast (Entry 4 of 5)

1 : the practice of fasting

2 : a time of fasting

fast

noun (2)

Definition of fast (Entry 5 of 5)

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

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Choose the Right Synonym for fast

Adjective

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

Adjective

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.

Examples of fast in a Sentence

Adjective

She's a very fast runner. We're off to a fast start. We're now experiencing a faster rate of inflation. We took the faster route.

Adverb

The boss expects this to be done this afternoon, so you'd better work fast. He ran as fast as he could. This is fast becoming a national problem. You need to act fast to take advantage of this offer. I don't know what caused the accident. It all happened so fast. She's a woman who can think fast in a crisis. He's going to have to talk fast to get himself out of this mess. The window was stuck fast. She held fast to her belief in justice. We must stand fast and not surrender!

Verb

She always fasts on Yom Kippur. Patients must fast for six hours before having the procedure.
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First Known Use of fast

Adjective

before the 12th century, in the meaning defined at sense 1a

Adverb

before the 12th century, in the meaning defined at sense 1

Verb

before the 12th century, in the meaning defined at sense 1

Noun (1)

before the 12th century, in the meaning defined at sense 1

Noun (2)

15th century, in the meaning defined above

History and Etymology for fast

Adjective

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

Adverb

see fast entry 1

Verb

Middle English, from Old English fæstan

Noun (1)

see fast entry 3

Noun (2)

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

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Statistics for fast

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Time Traveler for fast

The first known use of fast was before the 12th century

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More Definitions for fast

fast

adjective

English Language Learners Definition of fast

 (Entry 1 of 3)

: moving or able to move quickly

: happening quickly : taking a short amount of time

: operating quickly

fast

adverb

English Language Learners Definition of fast (Entry 2 of 3)

: 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

English Language Learners Definition of fast (Entry 3 of 3)

: to eat no food for a period of time

fast

adjective
\ˈfast \
faster; fastest

Kids Definition of fast

 (Entry 1 of 4)

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

fast

adverb
faster; fastest

Kids Definition of fast (Entry 2 of 4)

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.

fast

verb
fasted; fasting

Kids Definition of fast (Entry 3 of 4)

1 : to go without eating

2 : to eat in small amounts or only certain foods

fast

noun

Kids Definition of fast (Entry 4 of 4)

1 : the act of going without food

2 : a time when no food is eaten

fast

adjective
\ˈfast \

Medical Definition of fast 

(Entry 1 of 3)

1 : firmly fixed

2a : 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

Medical Definition of fast (Entry 2 of 3)

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 hypnoticLancet

fast

noun

Medical Definition of fast (Entry 3 of 3)

1 : the practice of fasting

2 : a time of fasting

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More from Merriam-Webster on fast

Rhyming Dictionary: Words that rhyme with fast

Thesaurus: All synonyms and antonyms for fast

Spanish Central: Translation of fast

Nglish: Translation of fast for Spanish Speakers

Britannica English: Translation of fast for Arabic Speakers

Britannica.com: Encyclopedia article about fast

Comments on fast

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