fast

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."

Primary Meanings of fast

1.
adjadv
acting or moving or capable of acting or moving quickly
quickly or rapidly (often used as a combining form)
2.
adjadv
securely fixed in place
firmly or closely
3.
adj
(used of timepieces) indicating a time ahead of or later than the correct time
4.
adj
(of surfaces) conducive to rapid speeds
5.
adj
unrestrained by convention or morality
6.
vn
abstain from eating
abstaining from food
Full Definitions of fast
1

adj acting or moving or capable of acting or moving quickly

fast film”
“on the fast track in school”
“set a fast pace”
“a fast car”
Synonyms:
accelerated
speeded up, as of an academic course
alacritous
quick and eager
blistering, hot, red-hot
very fast; capable of quick response and great speed
double-quick
(of a marching cadence) very quick
express
without unnecessary stops
fast-breaking
occurring rapidly as a series of events in rapid succession
fast-paced
of communication that proceeds rapidly
fleet, swift
moving very fast
high-speed, high-velocity
operating at high speed
hurrying, scurrying
moving with great haste
immediate, prompt, quick, straightaway
performed with little or no delay
instant, instantaneous
occurring with no delay
meteoric
like a meteor in speed or brilliance or transience
quick, speedy
accomplished rapidly and without delay
rapid
done or occurring in a brief period of time
rapid, speedy
characterized by speed; moving with or capable of moving with high speed
smart
quick and brisk
winged
very fast; as if with wings
windy
resembling the wind in speed, force, or variability
sudden
happening without warning or in a short space of time
hurried
moving rapidly or performed quickly or in great haste
Antonyms:
slow
not moving quickly; taking a comparatively long time
bumper-to-bumper
used of traffic
dilatory, laggard, pokey, poky
wasting time
drawn-out
(used of speech) uttered slowly with prolonged vowels
lazy
moving slowly and gently
long-play, long-playing
(used of records) playing at a slower speed and for a longer time than earlier records
slow-moving
moving slowly
sluggish, sulky
moving slowly
gradual
proceeding in small stages
unhurried
relaxed and leisurely; without hurry or haste
show more antonyms...

adj at a rapid tempo

“the band played a fast fox trot”
Synonyms:
allegro
(of tempo) fast
allegretto
(of tempo) faster than allegro
andantino
(of tempo) moderately fast
presto
(of tempo) very fast
prestissimo
(of tempo) as fast as possible
vivace
(of tempo) very fast and lively
Antonyms:
slow
at a slow tempo
adagio
(of tempo) leisurely
andante
(of tempo) moderately slow
lento
(of tempo) slow
lentissimo
(of tempo) very slow
largo
very slow in tempo and broad in manner
larghetto
(of tempo) less slow and broad than largo
larghissimo
(of tempo) as slow and broad as possible
moderato
(of tempo) moderate
show more antonyms...

adj hurried and brief

“a fast visit”
Synonyms:
flying, quick
hurried
moving rapidly or performed quickly or in great haste

adj (of a photographic lens or emulsion) causing a shortening of exposure time

“a fast lens”
Synonyms:
causative
producing an effect

adv quickly or rapidly (often used as a combining form)

“how fast can he get here?”
“ran as fast as he could”
“needs medical help fast
fast-running rivers”
fast-breaking news”
fast-opening (or fast-closing) shutters”
2

adj securely fixed in place

Synonyms:
firm, immobile
fixed
securely placed or fastened or set

adj resistant to destruction or fading

fast colors”
Synonyms:
imperviable, impervious
not admitting of passage or capable of being affected

adj unwavering in devotion to friend or vow or cause

fast friends”
Synonyms:
firm, loyal, truehearted
faithful
steadfast in affection or allegiance

adv firmly or closely

“held fast to the rope”
“her foot was stuck fast
Synonyms:
tight
3

adj (used of timepieces) indicating a time ahead of or later than the correct time

“my watch is fast
Antonyms:
slow
(used of timepieces) indicating a time earlier than the correct time
4

adj (of surfaces) conducive to rapid speeds

“a fast road”
Synonyms:
smooth
having a surface free from roughness or bumps or ridges or irregularities
5

adj unrestrained by convention or morality

fast women”
Synonyms:
debauched, degenerate, degraded, dissipated, dissolute, libertine, profligate, riotous
immoral
deliberately violating accepted principles of right and wrong
6

v abstain from eating

“Before the medical exam, you must fast
Types:
diet
eat sparingly, for health reasons or to lose weight
Type of:
abstain, desist, refrain
choose not to consume

v abstain from certain foods, as for religious or medical reasons

“Catholics sometimes fast during Lent”
Types:
diet
follow a regimen or a diet, as for health reasons
Type of:
abstain, desist, refrain
choose not to consume

n abstaining from food

Synonyms:
fasting
Types:
diet, dieting
the act of restricting your food intake (or your intake of particular foods)
hunger strike
a voluntary fast undertaken as a means of protest
Ramadan
(Islam) a fast (held from sunrise to sunset) that is carried out during the Islamic month of Ramadan
Type of:
abstinence
act or practice of refraining from indulging an appetite

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