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reflex

reflex

99 3.7
A quick action you do without thinking in response to something
  • noun
  • /ˈriːflɛks/
: reflejo
  • When the doctor tapped his knee, the reflex made his leg kick out unexpectedly.
  • reflex arc
  • orienting reflex
  • vestibulo-ocular reflex

It's a great game for observation, for reflexes, for concentration as well.

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Examples

  • His quick reflex allowed him to catch the ball before it hit the ground.

  • Uncontrollably, her whole body starts to shake, and as if by reflex, ADA begins to walk.

    Fiction book (1993)
  • - Sorry, it's a reflex action.

  • That was a reflex action in the heat of the moment.

  • It's just a reflex action.

  • It was a reflex action.

  • The boy's hand sprang up by reflex, and his face broke into a smile.

    Fiction book (1990)
  • It was an involuntary reflex.

  • Anya's eyes flash open and, totally on reflex, she belts Dmitri in the nose.

    Fiction book (1997)
  • The sudden loud noise caused her to flinch in reflex, even though she knew it was just a car backfiring.

Synonyms

gut reaction
vsreflex
10 4.3

A strong first feeling you have without thinking

describes an automatic bodily act caused by a stimulus, not mainly emotion
reflex action
vsreflex
2 3.4

A quick movement your body makes without thinking, for example pulling your hand from something hot

emphasizes being instinctive and involuntary rather than learning status
physiological reaction
vsreflex
  • Specialized
1 4.5

An automatic body response to something that affects it, like sweating or a faster heartbeat

is the general term for involuntary acts, not limited to bodily changes
reflex response
vsreflex
1 4.2

An automatic action your body makes without thinking when something touches or moves near you

stresses involuntary bodily movement rather than any learned behaviour
1 5.1

A quick action you do without thinking

puts stronger stress on being involuntary and uncontrolled by thought
instinctive reflex
vsreflex
  • Specialized
1 4.0

An automatic body response to a touch or sound that happens without thinking

underscores involuntary and unconscious control rather than learning status
inborn reflex
vsreflex
  • Specialized
1 3.5

An automatic action a baby does without learning

applies generally to involuntary bodily acts beyond those present at birth
unconditioned reflex
vsreflex
  • Specialized
1 6.5

An automatic body response to a signal without learning

highlights instinctive, involuntary nature more than conditioning history
innate reflex
vsreflex
  • Specialized
1 4.1

An automatic action your body makes without being taught

focuses on involuntary, automatic nature rather than origin or timing

Antonyms

3 8.0

The ability to act on purpose and direct the mind toward a goal

learned response
  • Specialized
1 5.7

A reaction a person develops from practice or experience, not one they are born with

Compounds

gag reflex
  • Specialized
9 4.1

An automatic throat reaction that makes you feel like vomiting

A quick movement your body makes without thinking, for example pulling your hand from something hot

conditioned reflex
  • Specialized
1 5.3

An automatic response learned when a neutral sound or sign is repeatedly paired with something that naturally causes it

An automatic action your body makes without thinking when something touches or moves near you

A camera that lets you see and focus exactly what the lens shows before you take a photo

Babinski reflex
  • Specialized
1 6.8

Toes move up when the sole is touched, normal in babies but may show nerve damage in adults

pilomotor reflex
  • Specialized
1 7.7

An automatic body reaction that makes hairs stand up when you are cold, scared, or your skin is irritated

light reflex
  • Specialized
1 5.3

An automatic change that makes the pupil smaller in bright light or after some drugs

instinctive reflex
  • Specialized
1 4.0

An automatic body response to a touch or sound that happens without thinking

patellar reflex
  • Specialized
1 6.0

A quick kick of the lower leg after a tap below the kneecap

pupillary reflex
  • Specialized
1 7.0

An automatic narrowing of the pupil in bright light or after some medicines

reflex arc
  • Specialized
1 7.0

A path of nerve cells that sends quick signals for body reactions, like the knee-jerk

Moro reflex
  • Specialized
1 7.2

A new baby stretches the arms and pulls the legs in after a sudden loud noise or movement

stretch reflex
  • Specialized
1 6.5

An automatic muscle tightening that happens when a muscle is pulled

startle reflex
  • Specialized
1 5.1

A baby's quick arm and leg movement after a loud noise

inborn reflex
  • Specialized
1 3.5

An automatic action a baby does without learning

unconditioned reflex
  • Specialized
1 6.5

An automatic body response to a signal without learning

acquired reflex
  • Specialized
1 6.5

A learned automatic response to a signal, for example salivating at a bell

rooting reflex
  • Specialized
1 6.4

An automatic movement when someone touches a baby's cheek that makes them turn and open their mouth

innate reflex
  • Specialized
1 4.1

An automatic action your body makes without being taught

pharyngeal reflex
  • Specialized
1 8.8

A quick reaction that makes you retch or gag when the back of the throat is touched

suckling reflex
  • Specialized
1 5.9

An automatic movement in newborn animals like human babies that makes them find the mother's nipple and take milk

conditional reflex
  • Specialized
6.5

An automatic learned reaction to a signal after repeated practice, for example a dog drooling at a bell

6.7

An automatic body signal that makes you want to push out poo when your bottom is full

accommodation reflex
  • Specialized
6.5

The eye automatically changes the lens shape to focus on near and far objects

knee-jerk reflex
  • Specialized
3.9

A sudden automatic kick of the lower leg when the tendon below the kneecap is tapped

micturition reflex
  • Specialized
8.7

Automatic body action that makes you empty your bladder when it is full

monosynaptic reflex
  • Specialized
7.6

A fast automatic body response using one connection between the nerve that senses and the nerve that moves

myotactic reflex
  • Specialized
8.8

A muscle tightens when its tendon is stretched to help keep the body upright

rectal reflex
  • Specialized
6.7

A natural body response when stool in the rectum makes you want to use the toilet

reflex angle
  • Specialized
5.8

An angle larger than 180 degrees but smaller than 360 degrees

reflex epilepsy
  • Specialized
6.8

A condition that causes seizures when you see flashing lights or hear loud sounds

plantar reflex
  • Specialized
7.1

An automatic movement where the toes bend when the sole of the foot is stroked firmly, usually seen in adults

How Automatic

instinctive reflex
  • Specialized
1 4.0
reflex
99 3.7
learned response
  • Specialized
1 5.7

Surface Forms

reflex singular
reflexes plural

Morphology

reflex = flex (opaque) = re + flex

The prefix 're-' typically means 'again' or 'back', but in 'reflex', it doesn't follow the standard semantic logic.

Etymology

Reflex comes from the Latin parts re- 'back' and flectere 'to bend'. Like flex (to bend), a reflex is an automatic, natural response that happens without thinking, as when your body pulls back or moves after a touch or surprise.