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
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

But the siren song of an oversize single lens reflex (SLR) camera proved difficult to resist. Christopher Elliott, USA TODAY, "What is the best camera for a family vacation? The one you have with you in the moment," 15 July 2019 To succeed on the court, players need extraordinary hand-eye coordination and quick reflexes. David Lyons, sun-sentinel.com, "Goodbye horses, hello jai alai? Isle Casino Pompano looks to revive fast-paced game," 12 July 2019 This reflex is named after the vagus nerve, which runs from your brain to your heart, lungs and digestive tract. Anne R. Crecelius, The Conversation, "Why do people faint?," 20 June 2019 Scientifically speaking, this activates the mammalian diving reflex and kicks on your parasympathetic nervous system, which is responsible for relaxation. Melody Wilding, Quartz at Work, "How to control your emotions when you’re at work," 3 June 2019 For decades ahead, this fusion of human minds and machine reflexes will likely be the norm. Christopher Mims, WSJ, "Self-Driving Cars Have a Problem: Safer Human-Driven Ones," 15 June 2019 When he is faced with a challenge on the world stage, Trump’s reflex is to reach for economic carrots and sticks as a way to advance U.S. interests. John Walcott, Time, "The Risks of Trump’s Dollar-Driven Diplomacy," 13 June 2019 His cat like reflex saves often beggared belief, and he was voted Player of the Year at the conclusion of the 2001/02 season. SI.com, "Claudio Ranieri: The Tinkerman's All Time Best XI," 12 June 2019 After a lengthy bathroom break, Nadal stormed to the first 11 points and tallied a double break advantage with a reflex forehand pass. Ravi Ubha, CNN, "Ruthless Nadal beats Thiem to win record-extending 12th French Open," 9 June 2019

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

18 Jul 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
: 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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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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