reflex

1 of 2

noun

re·​flex ˈrē-ˌfleks How to pronounce reflex (audio)
1
a
archaic : reflected heat, light, or color
b
: a mirrored image
c
: a copy exact in essential or peculiar features
2
a
: 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

2 of 2

adjective

1
: directed back on the mind or its operations : introspective
2
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
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
The researchers speculated that the phenomenon could be comparable to other reflexes, like coughing or sneezing, that enable the spread of microbes. Deborah Balthazar, STAT, 22 Nov. 2023 This time, doctors diagnosed her with acute flaccid myelitis (AFM,) which the CDC says is a serious neurological condition that causes the muscles and reflexes in the body to become weak. Jordan Greene, Peoplemag, 2 Nov. 2023 But this garden variety reflex doesn't usually pique our interest. Cody Cottier, Discover Magazine, 9 Oct. 2023 Equally as impressive is its damping, which instinctively treads the line between comfort and sharp reflexes with balanced results. Andrew Wendler, Car and Driver, 12 July 2023 The authors argued that this was evidence the crabs experience some form of pain, rather than just a reflex. Emily Mullin, WIRED, 6 Oct. 2023 Almost all animals have a reflex for responding to noxious stimuli, called nociception, but not all are aware that the sensation is bad or unpleasant—an awareness scientists now think octopuses and other cephalopods have. Emily Mullin, WIRED, 6 Oct. 2023 The diligence and extraordinary reflexes brought him 15 Gold Gloves. Tom Krasovic, San Diego Union-Tribune, 5 Oct. 2023 Newborn Sleep: What to Expect Between Birth and 3 Months Physical development for 9-week-old babies As your baby develops more physical control, some newborn reactions—such as the Moro (or startle) reflex—will start to fade. Parents Editors, Parents, 3 Oct. 2023
Adjective
Related: Jarren Duran’s reflex reaction to injury ending what was fast becoming a successful season? Julian McWilliams, BostonGlobe.com, 8 Sep. 2023 Other times, the orcas force the sharks upside down, and a reflex triggers the fish into a paralysis-like state. Victoria Sayo Turner, Smithsonian Magazine, 12 July 2023 During that time, the other biologists woke her up, asked her questions and carried out reflex tests with her hands. Smithsonian Magazine, 10 July 2023 The rear reflex reflectors may detach. Detroit Free Press, 29 Aug. 2020 For instance, research published in Alternative Therapies in Health and Medicine found that massaging the reflex areas in our feet and hands, also known as ‘reflexology,’ can increase vagal tone and, in turn, decrease blood pressure and heart rate levels. Mark Travers, Forbes, 20 Feb. 2023 The cooking mechanic is just a light reflex game. Cecilia D'anastasio, Wired, 1 Oct. 2020 This year, in what many called a reflex response to California policies, a state law was fast-tracked through the Legislature and signed by the governor in February to prevent Arizona’s cities and towns from banning natural gas or other fossil fuels in buildings. Erin Stone, The Arizona Republic, 25 Sep. 2020 Meanwhile, the main woofer is a 5.5-inch aluminum alloy driver delivering a beefy bass response that can dip as low as 45Hz thanks to a reflex port on the rear of each cabinet. Mark Sparrow, Forbes, 29 Dec. 2022 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'reflex.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun

Latin reflexus, past participle of reflectere to reflect

Adjective

Latin reflexus

First Known Use

Noun

1508, in the meaning defined at sense 1a

Adjective

1607, in the meaning defined at sense 1

Time Traveler
The first known use of reflex was in 1508

Dictionary Entries Near reflex

Cite this Entry

“Reflex.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reflex. Accessed 7 Dec. 2023.

Kids Definition

reflex

1 of 2 noun
re·​flex ˈrē-ˌfleks How to pronounce reflex (audio)
1
: an automatic response to a stimulus in which a nerve message passes from a sense organ to the spinal cord and then to a point of action (as a muscle or gland) often without first passing to the brain
the knee-jerk reflex
compare habit sense 3
2
plural : the power of acting or responding with enough speed
an athlete with great reflexes

reflex

2 of 2 adjective
1
: produced in reaction, resistance, or return
2
: of, relating to, or produced by a reflex of the nervous system
reflex action
reflexly adverb

Medical Definition

reflex

1 of 2 noun
re·​flex ˈrē-ˌfleks How to pronounce reflex (audio)
1
a
: reflected heat, light, or color
b
: a mirrored image
2
a
: 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

2 of 2 adjective
1
: bent, turned, or directed back : reflected
2
: of, relating to, or produced by a reflex without intervention of consciousness
Last Updated: - Updated example sentences
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