verb (used with object)

to bend, as a part of the body: He flexed his arms to show off his muscles.
to tighten (a muscle) by contraction.

verb (used without object)

to bend.


the act of flexing.
  1. any flexible, insulated electric cord; an electric cord or extension cord.
  2. Slang.an elastic band, as a garter.
Mathematics. an inflection point.

Origin of flex

1515–25; (adj.) < Latin flexus, past participle of flectere to bend, turn; (noun) < Latin flexus act of bending, equivalent to flect(ere) + -tus suffix of v. action
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for flexing

tilt, tighten, lean, ply, angle, stretch, spring, curve, contract, crook, yield, mold

Examples from the Web for flexing

Contemporary Examples of flexing

Historical Examples of flexing

  • She sat and stared at the black letters, flexing the packet filled with bills.

    The Harbor of Doubt

    Frank Williams

  • First she stood tentatively, flexing her knees and testing her weight.

  • Flexing his hands until he worked some feeling into them, he inched the ship lower.

    Bolden's Pets

    F. L. Wallace

  • The flexing of the limbs is probably also an Upper Palolithic custom.

    Men of the Old Stone Age

    Henry Fairfield Osborn

  • Sine was flexing his muscles, sitting up with the support of one elbow.

    The Metal Moon

    Everett C. Smith

British Dictionary definitions for flexing



British a flexible insulated electric cable, used esp to connect appliances to mainsUS and Canadian name: cord
informal flexibility or pliability


to bend or be benthe 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)

Word Origin for flex

C16: from Latin flexus bent, winding, from flectere to bend, bow
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for flexing



1520s, probably a back-formation from flexible. Related: Flexed; flexing.

Online Etymology Dictionary, © 2010 Douglas Harper

flexing in Medicine




To bend.
To contract a muscle.
To move a joint so that the parts it connects approach each other.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.