fast
1 Americanadjective
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moving or able to move, operate, function, or take effect quickly; quick; swift; rapid: a fast pain reliever;
a fast horse;
a fast pain reliever;
a fast thinker.
- Antonyms:
- slow
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done in comparatively little time; taking a comparatively short time: fast work.
a fast race;
fast work.
- Antonyms:
- slow
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(of time)
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indicating a time in advance of the correct time, as of a clock.
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noting or according to daylight-saving time.
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adapted to, allowing, productive of, or imparting rapid movement: one of the fastest pitchers in baseball.
a hull with fast lines;
one of the fastest pitchers in baseball.
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characterized by unrestrained conduct or lack of moral conventions, especially in sexual relations; wanton; loose.
Some young people in that era were considered fast, if not downright promiscuous.
- Synonyms:
- prodigal, wild, immoral, profligate, dissolute, dissipated
- Antonyms:
- restrained
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characterized by hectic activity.
leading a fast life.
- Antonyms:
- restrained
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resistant.
acid-fast.
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firmly fixed in place; not easily moved; securely attached.
- Antonyms:
- loose
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held or caught firmly, so as to be unable to escape or be extricated.
an animal fast in a trap.
- Synonyms:
- inextricable
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firmly tied, as a knot.
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closed and made secure, as a door, gate, or shutter.
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such as to hold securely.
to lay fast hold on a thing.
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firm in adherence; loyal; devoted.
fast friends.
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permanent, lasting, or unchangeable: a hard and fast rule.
a fast color;
a hard and fast rule.
- Synonyms:
- enduring
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Informal.
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(of money, profits, etc.) made quickly or easily and sometimes deviously.
He earned some fast change helping the woman with her luggage.
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cleverly quick and manipulative in making money.
a fast operator when it comes to closing a business deal.
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Photography.
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(of a lens) able to transmit a relatively large amount of light in a relatively short time.
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(of a film) requiring a relatively short exposure time to attain a given density.
-
-
Horse Racing.
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(of a track condition) completely dry.
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(of a track surface) very hard.
-
adverb
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quickly, swiftly, or rapidly.
-
in quick succession.
Events followed fast upon one another to the crisis.
-
to hold fast.
- Synonyms:
- tenaciously, fixedly, securely
-
fast asleep.
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in a wild or dissipated way.
- Synonyms:
- prodigally, wildly, recklessly
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ahead of the correct or announced time.
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Archaic. close; near.
fast by.
noun
idioms
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pull a fast one, to play an unfair trick; practice deceit.
He tried to pull a fast one on us by switching the cards.
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play fast and loose. play.
verb (used without object)
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to abstain from all food.
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to eat only sparingly or of certain kinds of food, especially as a religious observance.
verb (used with object)
noun
-
an abstinence from food, or a limiting of one's food, especially when voluntary and as a religious observance; fasting.
-
a day or period of fasting.
noun
adjective
-
acting or moving or capable of acting or moving quickly; swift
-
accomplished in or lasting a short time
fast work
a fast visit
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(prenominal) adapted to or facilitating rapid movement
the fast lane of a motorway
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requiring rapidity of action or movement
a fast sport
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(of a clock, etc) indicating a time in advance of the correct time
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given to an active dissipated life
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of or characteristic of such activity
a fast life
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not easily moved; firmly fixed; secure
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firmly fastened, secured, or shut
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steadfast; constant (esp in the phrase fast friends )
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sport (of a playing surface, running track, etc) conducive to rapid speed, as of a ball used on it or of competitors playing or racing on it
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that will not fade or change colour readily
a fast dye
-
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proof against fading
the colour is fast to sunlight
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( in combination )
washfast
-
-
photog
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requiring a relatively short time of exposure to produce a given density
a fast film
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permitting a short exposure time
a fast shutter
-
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cricket (of a bowler) characteristically delivering the ball rapidly
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informal glib or unreliable; deceptive
a fast talker
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archaic sound; deep
a fast sleep
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informal a deceptive or unscrupulous trick (esp in the phrase pull a fast one )
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a person who achieves results quickly, esp in seductions
adverb
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quickly; rapidly
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soundly; deeply
fast asleep
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firmly; tightly
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in quick succession
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in advance of the correct time
my watch is running fast
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in a reckless or dissipated way
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archaic close or hard by; very near
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informal to behave in an insincere or unreliable manner
interjection
verb
noun
Synonym Usage
See quick.
Other Word Forms
Derived Forms
Conjugated Forms
Present
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have fastedperfect
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has fastedperfect 3rd person singular
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is fastingprogressive 3rd person singular
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has been fastingperfect progressive 3rd person singular
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are fastingprogressive
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am fastingprogressive 1st person singular
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have been fastingperfect progressive
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fastssingular 3rd person
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fastingparticiple
Past
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had fastedperfect
-
was fastingprogressive singular
-
had been fastingperfect progressive
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were fastingprogressive plural
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fastedsimple
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fastedparticiple
Future
Etymology
Origin of fast1
First recorded before 900; Middle English; Old English fæst “firm”; cognate with Dutch vast, Old Norse fastr “firm,” German fest; akin to fast 2
Origin of fast2
First recorded before 1000; Middle English fasten, festen, Old English fæstan; cognate with German fasten, Gothic fastan, Old Norse fasta
Origin of fast3
First recorded in 1670–80; alteration, by association with fast 1 ( def. ) (in the sense “firmly tied”), of late Middle English fest “fastening, mooring rope,” from Old Norse festr “mooring rope, cable,” from Old Norse fastr “fixed, firm”; cf. fasten, fast 1
Explanation
When you see fast, you might think of Olympic runner Usain "Lightning" Bolt or a Porsche 911 Turbo. Alternatively, and quite confusingly, fast also means to refrain from eating for a certain period, usually for religious reasons. Fast is another of those deceptively simple words that have a number of other meanings beyond their most common usages. If something "sticks fast" it means it cannot be removed — like a leech or a stain. "To stand fast" means not to give up your point of view or to remain loyal. Then there's also the slang meaning of living beyond the constraints of normal behavior — as in "the fast life," "the fast track," or "the fast lane."
Vocabulary lists containing fast
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
With FAST, residuals are determined by actual viewership, not potential viewership.
From Los Angeles Times • Oct. 26, 2023
Without analyses like FAST, reconstruction funding can often be directed to those with the greatest influence, who perhaps need the least support.
From Science Daily • Oct. 25, 2023
Reuters was not able to determine the extent of the cuts to the silicon unit, called Facebook Agile Silicon Team, or FAST, which has roughly 600 employees, according to the other source.
From Reuters • Oct. 3, 2023
Thanks to the unprecedented sensitivity of FAST, it can catch less energetic pulses that other telescopes cannot, says Di Li, the paper’s lead author and FAST’s chief scientist.
From Scientific American • Oct. 13, 2021
"I just got mine and all I can tell you is it works fast. And by fast, I mean FAST."
From "The Sky at Our Feet" by Nadia Hashimi
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.