noun
reflex
REEF-lehks
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 notesIn 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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Etymology
From Late Latin reflexus ("a bending back"), from reflectere ("to bend back").