reflex

noun
re·​flex | \ ˈrē-ˌfleks How to pronounce reflex (audio) \

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
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 Blinking, also known as the cornea reflex, is our brains’ automatic response when anything comes too near our eyes that could potentially be damaging. New York Times, "In the Blink of an Eye," 7 May 2020 If the ultimate goal is to reduce how human drivers cause harm with their inattention or slow reflexes, our immediate future is more like a pair of great eyeglasses than a full robot suit. Caroline Delbert, Popular Mechanics, "Elon Musk Says His Teslas Can Be Superhuman," 9 Apr. 2020 Most of the wildest, reverse-the-polarities ways that figures like Brown have proposed to forestall catastrophe tread on sensitive spots in the brain: flinch reflexes, squeamishness, areas of dizzying ignorance. Virginia Heffernan, Wired, "What Plant-Based Burgers Can Teach Us About Saving the Planet," 1 Apr. 2020 Third base: Rey — The former scavenger has power and quick reflexes, perfect for the hot corner. Jesse Yomtov, USA TODAY, "The All-Star Wars baseball team: Should Kylo Ren be a closer?," 20 Dec. 2019 Pickle juice may trigger a reflex in the mouth that sends a signal to the nerves to stop muscles from cramping. Cindy Krischer Goodman, sun-sentinel.com, "Pickle juice is a big dill for athletes. Here’s why they’re chugging it," 3 Dec. 2019 Our new reflexes, which might have seemed irrational a month ago, are quite acceptable now, even useful—not for watching Die Hard, but for navigating the outside world. Marina Koren, The Atlantic, "The New Cringeworthy," 17 Apr. 2020 From a pistol barrel, the 5.7 has ballistics similar to that of a .22 WMR rifle (like a 40-grain V-Max at 2,000 fps.+), and the Ruger comes drilled and tapped for a reflex-style optic of your choice. Will Brantley, Field & Stream, "Best New Hunting and Trail Handguns from the 2020 SHOT Show," 3 Feb. 2020 At home in the city: With his Rolleiflex twin-lens reflex, Akinbode Akinbiyi has captured the pulse of cities in Africa, the U.S., and Europe. National Geographic, "Are you one of our 132 million Instagram followers?," 20 Mar. 2020 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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Time Traveler for reflex

Time Traveler

The first known use of reflex was in 1508

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Statistics for reflex

Last Updated

22 May 2020

Cite this Entry

“Reflex.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reflex. Accessed 3 Jun. 2020.

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More Definitions for reflex

reflex

noun
How to pronounce reflex (audio)

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
: the natural ability to react quickly

reflex

noun
re·​flex | \ ˈrē-ˌfleks How to pronounce reflex (audio) \

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 How to pronounce reflex (audio) \

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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Comments on reflex

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