reflex

[ adjective, noun ree-fleks; verb ri-fleks ]

See synonyms for: reflex reflexes on Thesaurus.com

adjective

Physiology. noting or pertaining to an involuntary response to a stimulus, the nerve impulse from a receptor being transmitted inward to a nerve center that in turn transmits it outward to an effector.
occurring in reaction; responsive.

cast back; reflected, as light, color, etc.
bent or turned back.
designating a radio apparatus in which the same circuit or part performs two functions.

noun

Physiology.
- Also called reflex act . movement caused by a reflex response.
- Also called reflex action. the entire physiological process activating such movement.
any automatic, unthinking, often habitual behavior or response.

the reflection or image of an object, as exhibited by a mirror or the like.
a reproduction, as if in a mirror.
a copy; adaptation.
reflected light, color, etc.
Historical Linguistics. an element in a language, as a sound, that has developed from a corresponding element in an earlier form of the language: The (ō) in “stone” is a reflex of Old English ā.
a reflex radio receiver.
a reflex camera.

verb (used with object)

to subject to a reflex process.
to bend, turn, or fold back.

to arrange in a reflex system.

Origin of reflex

1500–10; <Latin reflexus bent back, past participle of reflectere to reflect

Other words from reflex

re·flex·ly, adverb
re·flex·ness, noun
mul·ti·re·flex, noun
sem·i·re·flex, noun

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use reflex in a sentence

Even if I were to be shot, the reflex action of my fingers would pull the trigger of this revolver and McGinty will die.
Hooded Detective, Volume III No. 2, January, 1942 | Various
The reflex action on his sensitive mind first stunned, and then warped his senses.
Etidorhpa or the End of Earth. | John Uri Lloyd
Such a physiological relation of things is termed reflex action.
Voice Production in Singing and Speaking | Wesley Mills
It is difficult to judge of any course of conduct entirely on its own merits, when it has a reflex action on ourselves.
The Arbiter | Lady F. E. E. Bell
She swears entirely by reflex action now, and believes in universal Nothwendigkeit.
The Letters of William James, Vol. 1 | William James

British Dictionary definitions for reflex

reflex

noun(ˈriːflɛks)

- an immediate involuntary response, esp one that is innate, such as coughing or removal of the hand from a hot surface, evoked by a given stimulus
- (as modifier): a reflex action See also reflex arc
- a mechanical response to a particular situation, involving no conscious decision
- (as modifier): a reflex response

a reflection; an image produced by or as if by reflection
a speech element derived from a corresponding form in an earlier state of the language: "sorrow" is a reflex of Middle English "sorwe"

adjective(ˈriːflɛks)

maths (of an angle) between 180° and 360°
(prenominal) turned, reflected, or bent backwards

verb(rɪˈflɛks)

(tr) to bend, turn, or reflect backwards

Origin of reflex

C16: from Latin reflexus bent back, from reflectere to reflect

Derived forms of reflex

reflexible, adjective
reflexibility, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for reflex

reflex

[ rē′flĕks′ ]

An involuntary physiological response to a stimulus, as the withdrawal of a body part from burning heat.
An unlearned or instinctive response to a stimulus. Also called unconditioned response See more at classical conditioning.

Cultural definitions for reflex

reflex

An action or movement not controlled by conscious thought. A reflex may be anything from a hiccup to the involuntary response of a body part, such as the action that occurs in the knee-jerk reflex.

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