1

reflex

noun re·flex \ ˈrē-ˌfleks \
Updated on: 16 Nov 2017

Definition of reflex

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

Examples of reflex in a Sentence

  1. reflexes such as swallowing and blinking

  2. Disagreeing with my suggestions has become almost a reflex for him.

  3. an athlete with great reflexes

  4. My reflexes are slower now that I'm older.

Recent Examples of reflex from the Web

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.

Origin and Etymology of reflex

Latin reflexus, past participle of reflectere to reflect


2

reflex

adjective

Definition of reflex

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

reflexly

adverb

Recent Examples of reflex from the Web

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.

Origin and Etymology of reflex

Latin reflexus


REFLEX Defined for English Language Learners

reflex

noun

Definition of reflex for English Language Learners

  • : 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

  • reflexes : the natural ability to react quickly


REFLEX Defined for Kids

reflex

noun re·flex \ ˈrē-ˌfleks \

Definition of reflex for Students

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.

Medical Dictionary

1

reflex

noun re·flex \ ˈrē-ˌfleks \

medical Definition of reflex

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

2

reflex

adjective

medical Definition of reflex

1 :bent, turned, or directed back :reflected
2 :of, relating to, or produced by a reflex without intervention of consciousness


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