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

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.
Recent Examples on the Web: Noun My love for standing out suppressed my anxiety, a reflex that turned out to be perfect for modeling. Marc Myers, WSJ, 9 Aug. 2022 Some people are more sensitive to this reflex than others. Anna Kaufman, USA TODAY, 12 July 2022 Democrats and their media pals often like to pretend that opposing tax hikes on corporations is merely a Republican political reflex. James Freeman, WSJ, 3 Aug. 2022 At the end of the exhalation, simply release the abdominal tension, so inhalation occurs as a reflex. Carol Kinsey Goman, Forbes, 6 June 2022 There’s the further, insider virtue that the square shape recalls that of prints from a much-loved classic camera, the Rolleiflex twin-lens reflex. Mark Feeney, BostonGlobe.com, 25 May 2022 Whereas for him this is almost a reflex that is part of his decision-making process. Washington Post, 11 Apr. 2022 Another issue is that for brands and retailers alike, leveraging value is a somewhat rusty reflex. Jon Bird, Forbes, 14 Mar. 2022 The reflex is to assume that the more expensive version is better. Dan Neil, WSJ, 19 May 2022 Recent Examples on the Web: Adjective After high school, Osman was working as a preschool teacher, and was tasked with taking photos of the children using a reflex camera. Jacopo Prisco, CNN, 27 May 2022 Muscle tension is almost a reflex reaction to stress—the body’s way of guarding against injury and pain. Laken Brooks, Forbes, 28 Dec. 2021 Except in the case of reflex actions, all muscle work begins with an act of conscious willing. Matt Fitzgerald, Outside Online, 19 Jan. 2021 Maddie still wasn't responding to the manual pain and reflex assessments. Jeff Nelson, PEOPLE.com, 13 Jan. 2022 With reflex syncope, her body is unable to appropriately regulate her heart rate and blood pressure, leading to dizziness, nausea, and a loss of consciousness. Jeneé Osterheldt, BostonGlobe.com, 8 Dec. 2021 If the variant was unexpected, the reflex reaction was not. Washington Post, 2 Dec. 2021 There’s also a rear reflex port to extend the speaker’s bass response. Mark Sparrow, Forbes, 5 Nov. 2021 Baby Carmen is set to go home with her dad on Monday after spending two months at the hospital due to reflex issues with her feedings, a common problem in many premature babies. Alaa Elassar, CNN, 24 Oct. 2021 See More

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.

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

Learn More About reflex

Dictionary Entries Near reflex

reflet

reflex

reflex arc

See More Nearby Entries 

Statistics for reflex

Last Updated

19 Aug 2022

Cite this Entry

“Reflex.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reflex. Accessed 19 Aug. 2022.

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More Definitions for reflex

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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