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 But as Covid-19 has ravaged elder-care facilities in the US and around the globe, advocates are now increasingly asking whether the reflex toward institutionalized care for seniors is due for a drastic rethinking, too. Michael Schulson, Quartz, "Coronavirus is renewing a call to abolish nursing homes," 25 June 2020 This entry-level option comes with a balanced dome tweeter, a two-way bass reflex design and can be installed either vertically or horizontally to fit your outdoor space. Shayna Murphy, USA TODAY, "Yamaha's outdoor speakers will outperform your portable Bluetooths—and they're on sale," 25 June 2020 In other words, everything that comes as a matter of reflex in baseball is suddenly off limits. Kevin Sherrington, Dallas News, "MLB finally made progress toward starting a season, but the problems it still faces are staggering," 23 June 2020 This reflex to police violence against peaceful citizens highlights the fact that the protests are not in response to one incident but rather the pervasive pattern of police violence against Black and Brown people. Aderonke Oguntoye, Essence, "How To Cope With Trauma In A Time Of Civil Unrest," 9 June 2020 Dogs have different areas that tickle their scratch reflex. Southern Living Editors, Southern Living, "Are Dogs Ticklish? Here’s What to Know About Scratching That Good Spot," 6 June 2020 The position of the testes is a reflex controlled by the cremaster muscle, which brings them closer to the body in colder temperatures to maintain the warmth needed for sperm production. Bill Sullivan, The Conversation, "Science of ‘Seinfeld’," 5 June 2020 And that reflex is rewarded in the fervor of his base. Brian Bennett, Time, "Trump's Divisive Instincts Helped Him Win the White House. Where Will They Take America Now?," 31 May 2020 This virus has halted the routine of the day to day and impelled us, in a rare reflex from our usual hustling, to seek purification. Paul Theroux, New York Times, "Paul Theroux Recalls a Fear-Filled Lockdown," 30 Mar. 2020 Recent Examples on the Web: Adjective Nikon has long made some of the best optics in the world, but this P-Tactical Spur is the company's first foray into reflex sights. The Editors, Outdoor Life, "The Outdoor Life Father’s Day Gift Guide," 1 June 2020 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

1 Jul 2020

Cite this Entry

“Reflex.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reflex. Accessed 4 Jul. 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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