flex·ion | \ˈflek-shən \

Definition of flexion 

1 : the act of flexing or bending

2 : a part bent : bend

4a : a bending movement around a joint in a limb (such as the knee or elbow) that decreases the angle between the bones of the limb at the joint — compare extension sense 3b

b : a forward raising of the arm or leg by a movement at the shoulder or hip joint

Examples of flexion in a Sentence

Recent Examples on the Web

Single-Leg Deadlift Improves: Hamstring strength for hip extension and knee flexion through each stroke Hold a free weight in your right hand and let your left foot hover above the floor putting most of your weight in your right foot. Philly.com, "4 essential strength training moves for cyclists," 5 June 2018 Accelerating down the runway will put some flexion into the wings, likely giving them a bit of a flapping quality as the plane takes off. Michael Belfiore, Popular Mechanics, "Say Hello to Stratolaunch, the World's Largest Plane," 17 Apr. 2012 Over a career spanning more than five decades and some 30 books, Roth’s themes were elaborated: lust, Jewishness in its New World colorations, and the large flexions of history that rose from the alignment of the two. Nathan Heller, Vogue, "Remembering Philip Roth, Literary Risk-Taker," 23 May 2018 The good news, though, was that her tendon sheaths, which facilitate the movement of the tendons and flexion of the limbs, had been spared. Jonas Shaffer, baltimoresun.com, "Red Ruby wins Black-Eyed Susan at Pimlico," 19 May 2018 Analysis will show the perfect center of gravity, the perfect circumference of the right thigh versus the left, the ideal size of the multifidus, the proper flexion of one ankle over another, the most efficient rotation of each hip. John Branch, New York Times, "Short-Track Speedskaters Are Lopsided," 20 Feb. 2018 What this means is that during the forward lunge, as the front foot hits the ground, the body's momentum moves forward, which may increase the angle of the knee flexion, explains Perkins. Jenny Mccoy, SELF, "The Difference Between Forward and Reverse Lunges, and How to Choose Which to Do," 2 May 2018 At that point in his rehabilitation, he was focused on knee flexion and strengthening his leg. Rich Campbell, chicagotribune.com, "Bears' doubts about Cameron Meredith's knee lead them not to match Saints' offer sheet," 11 Apr. 2018 Pelvic tilt, 5-10 reps This movement opens up the spine with a gentle flexion and extension motion. NBC News, "To make your day better, stay in bed longer. Really.," 12 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'flexion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of flexion

1615, in the meaning defined at sense 1

History and Etymology for flexion

borrowed from Latin flexiōn-, flexiō "act of bending or curving," from flectere "to cause to go in a different direction, bend, curve" (of uncertain origin) + -tiōn-, -tiō, suffix of verbal action

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Time Traveler for flexion

The first known use of flexion was in 1615

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variants: also flection \ˈflek-shən \

Medical Definition of flexion 

1 : a bending movement around a joint in a limb (as the knee or elbow) that decreases the angle between the bones of the limb at the joint — compare extension sense 2

2 : a forward raising of the arm or leg by a movement at the shoulder or hip joint

More from Merriam-Webster on flexion

See words that rhyme with flexion

Britannica.com: Encyclopedia article about flexion

Comments on flexion

What made you want to look up flexion? Please tell us where you read or heard it (including the quote, if possible).


evasion of direct action or statement

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