flex
verb (used with object)
to bend, as a part of the body.
flex
1 American
[fleks]
/ flɛks /
verb (used with object)
-
flexes,
present (3rd person singular)
-
flexed,
past participle, past
-
flexing
present participle
-
to bend, as a part of the body.
He flexed his arms to show off his muscles.
-
to tighten (a muscle) by contraction.
-
to demonstrate (one’s ability, expertise, etc.).
She’s flexed her marketing skills for various clients in the publishing industry.
-
Slang. to boast or brag about; flaunt.
He’s just not into flexing his success.
verb (used without object)
-
flexes,
present (3rd person singular)
-
flexed,
past participle, past
-
flexing
present participle
-
to bend.
-
Slang. to boast or brag; show off.
In his rap lyrics he flexes about his fancy lifestyle.
noun
-
flexes
plural
-
the act of flexing.
-
Slang. a boast or brag.
It's not a flex, but we have the best burgers here.
-
British.
-
any flexible, insulated electric cord; an electric cord or extension cord.
-
Slang. an elastic band, as a garter.
-
-
Mathematics. an inflection point.
verb phrase
flex
2
American
[fleks]
/ flɛks /
adjective
flex-
3
American
Also
flexi-.
flex
British
/ flɛks /
noun
-
US and Canadian name: cord. a flexible insulated electric cable, used esp to connect appliances to mains
-
informal flexibility or pliability
verb
-
to bend or be bent
he flexed his arm
his arm flexed
-
to contract (a muscle) or (of a muscle) to contract
-
(intr) to work according to flexitime
-
to test or display (one's authority or strength)
Usage
What else does flex mean? Flex is a slang term meaning "to show off," whether it be your physique, your belongings, or some other thing you consider superior to those of others. The act of flexing is often criticized as a power move, considered arrogant and insincere.
Other Word Forms
Inflected Forms
Nouns
Participles
Conjugated Forms
Present
-
flexsimple
-
flexessimple
-
have flexedperfect
-
has flexedperfect
-
am flexingprogressive
-
are flexingprogressive
-
is flexingprogressive
-
have been flexingperfect progressive
-
has been flexingperfect progressive
Past
-
flexedsimple
-
had flexedperfect
-
was flexingprogressive
-
were flexingprogressive
-
had been flexingperfect progressive
Future
Etymology
Origin of flex1
First recorded in 1515–25; (adjective) from Latin flexus, past participle of flectere “to bend, turn”; (noun) from Latin flexus act of bending, equivalent to flect(ere) + -tus suffix of verbal action
Origin of flex2
Shortening of flexible
Explanation
When you flex something, you bend or contract it. To appear super tough, you might flex your archery bow while flexing your muscles. Things curve and bend when they flex, whether they're human joints or objects made of a bendable material like plastic or soft wood. Another way to flex is to tense or contract a muscle: "The weightlifter flexes her biceps." Experts suspect that flexible came first, from the Latin root flexibilis, "flexible, pliant, or yielding," and figuratively, "tractable, or easily influenced."
Vocabulary lists containing flex
Strike A Pose: Positions and Posture
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Dance - Introductory
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The Lemonade War
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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.
See Examples For:
Chimpanzees are highly capable tree trunk climbers, aided by ankles that can flex much farther than human ankles.
From Science Daily ● Aug. 31, 2026
A chance to flex your big vocabulary: Do you know which activity a pugilist engages in?
From Slate ● Aug. 17, 2026
Root, a veteran character actor probably best known for his comedic roles like the nebbish Milton in Mike Judge’s cult classic “Office Space,” has had rare opportunities to flex his dramatic chops.
From Los Angeles Times ● Aug. 11, 2026
He noted that for both sectors, there’s “concentrated supply, capacity that cannot flex quickly, order books extending into 2028, and the same hyperscaler budgets funding all of it.”
From MarketWatch ● Aug. 11, 2026
I caught my foot in the flex of the bedside lamp, and stumbled, the book falling from my hands on to the floor.
From "Rebecca" by Daphne du Maurier
Better day care, plentiful jobs at decent wages, flex- time and job sharing would all help to reduce the stresses on American households, which are overtaxed, overburdened and overwhelmed.
From Time Magazine Archive
The very exercise of the penalty kick strips away many parts of the game where Messi usually flexes his genius.
From The Wall Street Journal ● Jul. 8, 2026
The tensions come as the Google-owned television service flexes its market muscle.
From Los Angeles Times ● Oct. 2, 2025
The duo mirroring Hulk Hogan-style underarm bicep flexes after winning their semi-final was one of the defining images.
From BBC ● Aug. 21, 2025
"Imagine, for example, a heart implant that bends and flexes with each heartbeat but still lasts for years."
From Science Daily ● Nov. 27, 2024
He flexes his right wrist and I notice that his hand is bandaged.
From "The Sun Is Also a Star" by Nicola Yoon
When the researchers deliberately flexed the membrane, they observed stable voltage signals.
From Science Daily ● Aug. 31, 2026
Curry flexed his versatile acting through more than Frank-N-Furter’s showy elevator debut and his vulnerable “I’m Going Home” finale.
From Los Angeles Times ● Aug. 26, 2026
Except for when passengers, after taking turns at rigging, filed below deck to explore the ship’s white-oak skeleton, which flexed and creaked in the current—the ancient sounds of a seafaring world that’s all but lost.
From The Wall Street Journal ● Jul. 15, 2026
Last year, it flexed its economic and diplomatic muscle, responding to Trump with tit-for-tat tariffs and restricting the export of rare earth minerals essential for advanced manufacturing.
From BBC ● May 14, 2026
It was still purple and the cuts were still evident, but he flexed it a few times without much pain.
From "We'll Fly Away" by Bryan Bliss
“They’re just flexing the trip rather than not going on the trip.”
From MarketWatch ● Aug. 12, 2026
Dos Santos did some vein-popping flexing on the sideline.
From Los Angeles Times ● Jul. 18, 2026
Local and state law enforcement officers will be "flexing" in those areas to ensure crowd safety, Mullin added, noting: "The games are going to be very secure."
From Barron's ● Jun. 11, 2026
Labor economists and union supporters said union victories in New York City could be hard to replicate elsewhere, but across the country unions have been flexing a bit more muscle in recent years.
From The Wall Street Journal ● May 20, 2026
“Who are you?” he asked, slowly flexing every part of his body to see how strong his bindings were.
From "Half Upon a Time" by James Riley
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.
