reflex(n = noun.act) inborn reflex, innate reflex, instinctive reflex, physiological reaction, reflex action, reflex response, unconditioned reflex - an automatic instinctive unlearned reaction to a stimulus;
is a kind of reaction, response
has particulars: accommodation reflex, babinski, babinski reflex, babinski sign, belch, belching, burp, burping, eructation, blink, blinking, eye blink, nictation, nictitation, wink, winking, blush, flush, disgorgement, emesis, puking, regurgitation, vomit, vomiting, defecation reflex, rectal reflex, oscitance, oscitancy, yawn, yawning, electric shock, electrical shock, shock, breaking wind, fart, farting, flatus, wind, gulp, gulping, knee-jerk reflex, knee jerk, patellar reflex, light reflex, miosis, myosis, pupillary reflex, mydriasis, micturition reflex, gag reflex, pharyngeal reflex, goose bump, goose pimple, goose skin, goosebump, gooseflesh, horripilation, pilomotor reflex, plantar reflex, rooting reflex, jump, start, startle, myotactic reflex, stretch reflex, suckling reflex, shake, shiver, tremble, sneeze, sneezing, sternutation, hiccough, hiccup, singultus
Derived form adjective reflex₁

   reflex(s = adj.all) automatic, reflexive - without volition or conscious control; "the automatic shrinking of the pupils of the eye in strong light"; "a reflex knee jerk"; "sneezing is reflexive"
Derived form noun reflex₁

1.  Directed back; attended by reflection; retroactive; introspective. [1913 Webster]
"The reflex act of the soul, or the turning of the intellectual eye inward upon its own actions." [1913 Webster]

2.  Produced in reaction, in resistance, or in return. [1913 Webster]

3.  Of, pertaining to, or produced by, stimulus or excitation without the necessary intervention of consciousness. [1913 Webster]

1.  Reflection; the light reflected from an illuminated surface to one in shade. [1913 Webster]
"Yon gray is not the morning's eye,
'Tis but the pale reflex of Cynthia's brow." [1913 Webster]
"On the depths of death there swims
The reflex of a human face." [1913 Webster]

2.  An involuntary movement produced by reflex action. [1913 Webster]

1.  To reflect. Shak. [1913 Webster]

2.  To bend back; to turn back. J. Gregory. [1913 Webster]

reflex, adj. & n.
--adj.
1 (of an action) independent of the will, as an automatic response to the stimulation of a nerve (e.g. a sneeze).
2 (of an angle) exceeding 180°.
3 bent backwards.
4 (of light) reflected.
5 (of a thought etc.) introspective; directed back upon itself or its own operations.
6 (of an effect or influence) reactive; coming back upon its author or source.
--n.
1 a reflex action.
2 a sign or secondary manifestation (law is a reflex of public opinion).
3 reflected light or a reflected image.
4 a word formed by development from an earlier stage of a language.

Idiom:
reflex arc Anat. the sequence of nerves involved in a reflex action. reflex camera a camera with a ground-glass focusing screen on which the image is formed by a combination of lens and mirror, enabling the scene to be correctly composed and focused.

Derivative:
reflexly adv.

Etymology:
L reflexus (as REFLECT)

N  copy, facsimile, counterpart, effigies, effigy, form, likeness, image, picture, photo, xerox, similitude, semblance, ectype, photo offset, electrotype, imitation, model, representation, adumbration, study, portrait, resemblance, duplicate, reproduction, cast, tracing, reflex, reflexion, reflection, shadow, echo, transcript, transcription, recording, scan, chip off the old block, reprint, new printing, rechauffe, apograph, fair copy, parody, caricature, burlesque, travesty, travestie, paraphrase, derivative, derivation, modification, expansion, extension, revision, second edition, servile copy, servile imitation, plagiarism, counterfeit, fake, pasticcio, faithful, lifelike, close, conscientious, unoriginal, imitative, derivative.

N  recoil, reaction, retroaction, revulsion, bounce, rebound, ricochet, repercussion, recalcitration, kick, contrecoup, springing back, elasticity, reflection, reflexion, reflex, reflux, reverberation, rebuff, repulse, return, ducks and drakes, boomerang, spring, reactionist, elastic collision, coefficient of restitution, recoiling, refluent, repercussive, recalcitrant, reactionary, retroactive, on the rebound, on the recoil, for every action there is a reaction, equal in force and opposite in direction.

N  regress, regression, retrocession, retrogression, retrograduation, retroaction, reculade, retreat, withdrawal, retirement, remigration, recession, recess, crab-like motion, refluence, reflux, backwater, regurgitation, ebb, return, resilience reflection, reflexion (recoil), flip-flop, volte-face, counter motion, retrograde motion, backward movement, motion in reverse, counter movement, counter march, veering, tergiversation, recidivation, backsliding, fall, deterioration, recidivism, recidivity, reversal, relapse, turning point, receding, retrograde, retrogressive, regressive, refluent, reflex, recidivous, resilient, crab-like, balky, reactionary, back, backwards, reflexively, to the right about, a reculons, a rebours, revenons a nos moutons, as you were.

accommodation reflex, acquired reflex, babinski reflex, conditional reflex, conditioned reflex, defecation reflex, gag reflex, inborn reflex, innate reflex, instinctive reflex, knee-jerk reflex, light reflex, micturition reflex, moro reflex, myotactic reflex, patellar reflex, pharyngeal reflex, pilomotor reflex, plantar reflex, pupillary reflex, rectal reflex, reflex action, reflex angle, reflex arc, reflex camera, reflex epilepsy, rooting reflex, startle reflex, stretch reflex, suckling reflex, unconditioned reflex