reflex

noun
re·​flex | \ ˈrē-ˌfleks \

Definition of reflex

 (Entry 1 of 2)

1a archaic : reflected heat, light, or color
b : a mirrored image
c : a copy exact in essential or peculiar features
2a : an automatic and often inborn response to a stimulus that typically involves a nerve impulse passing inward from a receptor to the spinal cord and then passing outward from the spinal cord to an effector (such as a muscle or gland) without reaching the level of consciousness and often without passing to the brain the knee-jerk reflex
b : the process that culminates in a reflex and comprises reception, transmission, and reaction

called also reflex action

c reflexes plural : the power of acting or responding with adequate speed
d : a way of thinking or behaving
3 : a linguistic element (such as a word or sound) or system (such as writing) that is derived from a prior and especially an older element or system boat is the reflex of Old English bāt

reflex

adjective

Definition of reflex (Entry 2 of 2)

1 : directed back on the mind or its operations : introspective
2 : reflexed
3 : produced or carried out in reaction, resistance, or return
4 of an angle : being between 180° and 360°
5 : of, relating to, or produced by a reflex without intervention of consciousness

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Other Words from reflex

Adjective

reflexly adverb

Examples of reflex in a Sentence

Noun

reflexes such as swallowing and blinking Disagreeing with my suggestions has become almost a reflex for him. an athlete with great reflexes My reflexes are slower now that I'm older.
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Recent Examples on the Web: Noun

This reflex fades around the age of 6 to 12 months, but a human's desire for touch remains necessary throughout their lives. Carolyn Twersky, Seventeen, "Why Do Couples Hold Hands?," 4 Jan. 2019 In people with rosacea, these reflexes seem to be hair-trigger-sensitive and prolonged. Nadia Berenstein, SELF, "Holiday Parties Bring Out the Worst of My Rosacea," 19 Dec. 2018 Driving is a ridiculously complicated skill, requiring experience, attention, and reflexes. Dan Rosenbaum, Ars Technica, "Why driving is hard—even for AIs," 7 Dec. 2018 This allows nerve reflexes to travel along the Cardi B neural pathway to the Wiz Kalifa 30 percent faster, saving time and saving lives. Tyler Mccarthy, Fox News, "Sacha Baron Cohen tricks gun-rights advocates, politicians in first preview of new show 'Who Is America?'," 15 July 2018 In this summer of nightmare, with the bad news by no means all out, the gag reflex of many Catholics is entirely understandable. George Weigel, WSJ, "A Crisis—but Not of Faith," 30 Aug. 2018 If the muscle is stretched too quickly, Schroeder says, the spindles will initiate the stretch reflex. Alexa Tucker, SELF, "Everything You Need to Know About Whether You Should Actually Bother Stretching," 19 Aug. 2018 Getty ImagesADRIAN DENNIS Today the very windy winds of Windsor tested Kate Middleton's wardrobe-malfunction reflexes after Princess Eugenie's wedding. Sally Holmes, Marie Claire, "Kate Middleton Avoided a Wardrobe Malfunction at Princess Eugenie's Wedding," 12 Oct. 2018 The nation's gag reflexes were tested this week after a woman was caught on camera dipping a chicken tender into cola, then of course eating it. Fox News, "Gutfeld: It's the cry babies vs. the jerk," 8 Sep. 2018

Recent Examples on the Web: Adjective

One reason the finger must stay off the trigger is that the reflex action of the finger to surprise could cause a loaded gun to fire. Christine Cunningham, Alaska Dispatch News, "Gun-safety rules apply in the photo studio too," 18 July 2017 Sauvignon blancs and grüner veltliners are reflex choices and would be fine. David Tanis, New York Times, "My New Favorite Beans," 17 Mar. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'reflex.' 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 reflex

Noun

1508, in the meaning defined at sense 1a

Adjective

1607, in the meaning defined at sense 1

History and Etymology for reflex

Noun

Latin reflexus, past participle of reflectere to reflect

Adjective

Latin reflexus

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Statistics for reflex

Last Updated

17 Jan 2019

Look-up Popularity

Time Traveler for reflex

The first known use of reflex was in 1508

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More Definitions for reflex

reflex

noun

English Language Learners Definition of reflex

: an action or movement of the body that happens automatically as a reaction to something

: something that you do without thinking as a reaction to something

reflexes : the natural ability to react quickly

reflex

noun
re·​flex | \ ˈrē-ˌfleks \

Kids Definition of reflex

1 : an action or movement that is made automatically without thinking as a reaction to a stimulus
2 reflexes plural : the natural ability to react quickly A driver needs good reflexes.

reflex

noun
re·​flex | \ ˈrē-ˌfleks \

Medical Definition of reflex

 (Entry 1 of 2)

1a : reflected heat, light, or color
b : a mirrored image
2a : an automatic and often inborn response to a stimulus that involves a nerve impulse passing inward from a receptor to the spinal cord and thence outward to an effector (as a muscle or gland) without reaching the level of consciousness and often without passing to the brain the knee-jerk reflex
b : the process that culminates in a reflex and comprises reception, transmission, and reaction
c reflexes plural : the power of acting or responding with adequate speed

reflex

adjective

Medical Definition of reflex (Entry 2 of 2)

1 : bent, turned, or directed back : reflected
2 : of, relating to, or produced by a reflex without intervention of consciousness

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More from Merriam-Webster on reflex

Rhyming Dictionary: Words that rhyme with reflex

Spanish Central: Translation of reflex

Nglish: Translation of reflex for Spanish Speakers

Britannica English: Translation of reflex for Arabic Speakers

Britannica.com: Encyclopedia article about reflex

Comments on reflex

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