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noun Uncommon

reflex

REEF-lehks

Reflex (noun) means an automatic, involuntary response to a stimulus, happening without conscious thought. Example: “The doctor tapped his knee to test his reflexes.”

noun
1
An automatic, involuntary response to a stimulus, happening without conscious thought.
"The doctor tapped his knee to test his reflexes."
"Blinking is a natural reflex when something comes near your eyes."
adj
1
Happening automatically, without deliberate thought.
"Her reflex action was to duck when the ball flew at her."

How to Use Reflex

Learner’s notes

In plain EnglishAn automatic bodily reaction you don't consciously control, like blinking or flinching.

Common pairings
knee-jerk reflex quick reflexes reflex action

Word Forms

more reflex comparative, reflexed past tense, reflexes plural, reflexes singular, most reflex superlative

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The doctor tapped his knee to test his _____.

Etymology

From Late Latin reflexus ("a bending back"), from reflectere ("to bend back").

Origin: Late Latin

reflex action innate reflex inborn reflex reflex response instinctive reflex unconditioned reflex physiological reaction

Frequently Asked Questions

What does “reflex” mean?

The word “reflex” means an automatic, involuntary response to a stimulus, happening without conscious thought. In plain terms, an automatic bodily reaction you don't consciously control, like blinking or flinching.

How do you pronounce “reflex”?

“Reflex” is pronounced REEF-lehks (/ˈɹiːflɛks/ in IPA).

How do you use “reflex” in a sentence?

Here is “reflex” used in a sentence: “The doctor tapped his knee to test his reflexes.”

What part of speech is “reflex”?

Depending on how it is used, “reflex” can be a noun and an adjective.

Where does the word “reflex” come from?

The word “reflex” comes from Late Latin. From Late Latin reflexus ("a bending back"), from reflectere ("to bend back").

Is “reflex” a common word?

“Reflex” is an uncommon word in modern English.

How many meanings does “reflex” have?

“Reflex” has 2 distinct senses listed in this dictionary. The most common is: an automatic, involuntary response to a stimulus, happening without conscious thought.

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