fast

1 of 5

adjective

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 buckR. 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

fast

2 of 5

adverb

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

fast

3 of 5

verb

fasted; fasting; fasts

intransitive verb

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

fast

4 of 5

noun (1)

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

fast

5 of 5

noun (2)

: something that fastens (such as a mooring line) or holds a fastening
Choose the Right Synonym for 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

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.
Recent Examples on the Web
Adjective
Earlier this summer, McDonald’s kicked off a competition amongst fast food restaurants by coming out with a $5 Meal Deal on June 25. Miles Berry, Peoplemag, 10 July 2024 But Audra was unbothered and continued resting, so the zookeeper gave us some fast facts about the species. Grace Tucker, The Enquirer, 10 July 2024
Adverb
The research found that of glacier shrinkage in the area were five times faster from 2015 to 2019 than from 1948 to 1979. Dinah Voyles Pulver, USA TODAY, 12 July 2024 Certain items rust faster than others, especially those that are frequently exposed to moisture. Mary Cornetta, Better Homes & Gardens, 11 July 2024
Verb
How to Prevent Copper Tarnish Dry Items Thoroughly Copper tarnishes fasting when wet, so make sure to dry copper dishes immediately after washing them. Jan Soults Walker, Better Homes & Gardens, 10 July 2024 So our ability to learn on the fly, to build chemistry extremely fast, and to adapt and adjust every single game is going to be crucial. Alex Zietlow, Charlotte Observer, 10 July 2024
Noun
There are other versions, including the 16:8 fast, which involves fasting for 16 hours and then having an eight-hour window for eating, and the OMAD or One Meal A Day, which is a 23:1 pattern, where only one meal is consumed each day. Chas Newkey-Burden, The Week Uk, theweek, 12 June 2024 The researchers measured levels of xylitol in participants' blood after an overnight fast, and found that those with the highest levels had a two-fold greater risk of having a heart attack, stroke, or dying over three years compared to those with the lowest levels. Alice Park, TIME, 6 June 2024 See all Example Sentences for fast 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'fast.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Adjective and Adverb

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

Verb and Noun (1)

Middle English, from Old English fæstan

Noun (2)

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

First Known Use

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)

12th century, in the meaning defined at sense 1

Noun (2)

15th century, in the meaning defined above

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

Dictionary Entries Near fast

Cite this Entry

“Fast.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fast. Accessed 16 Jul. 2024.

Kids Definition

fast

1 of 4 adjective
1
a
: firmly fixed or bound
b
: tightly shut
c
: sticking firmly
2
: firmly loyal
became fast friends
3
a
: moving or able to move rapidly
b
: taking a short time
c
: giving quickness of motion (as to a thrown ball)
d
: favorable to speed
the faster route
4
: indicating ahead of the correct time
my clock is fast
5
: tricky and unfair
pulled a fast one
6
: not likely to fade
fast colors

fast

2 of 4 adverb
1
: in a fixed manner
stuck fast
2
: in a complete manner : soundly, deeply
fast asleep
3
: with great speed
a building fast going to ruin

fast

3 of 4 verb
1
: to go without eating
2
: to eat in small amounts or only certain foods

fast

4 of 4 noun
1
: the act of fasting
2
: a time of fasting
Etymology

Adjective

Old English fæst "firmly fixed"

Verb

Old English fæstan "to go without eating"

Medical Definition

fast

1 of 3 adjective
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

fast

2 of 3 intransitive verb
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

3 of 3 noun
1
: the practice of fasting
2
: a time of fasting

More from Merriam-Webster on fast

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