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knee-jerk

adjective \ ˈnē-ˌjərk , -ˈjərk \

Definition of knee-jerk

:readily predictable :automatic
  • knee-jerk reactions
; also,  disapproving :reacting in a readily predictable way
  • The man was such a bleeding-heart knee-jerk liberal that you could predict the rest of the column after reading the first sentence.
  • —Andrew M. Greeley

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First Known Use of knee-jerk

1951

knee-jerk Synonyms

Synonyms
instinctive, instinctual, involuntary, knee-jerk, mechanic, mechanical, robotic, spontaneous
Antonyms
nonmechanical
Related Words
conditioned, natural, Pavlovian, reactive, reflex, simple, subliminal, unconscious, unforced, visceral; blind, inadvertent, unintended, unintentional, unwilling, unwitting; abrupt, quick, ready, sudden; ad-lib, extemporaneous, extempore, impromptu, improvised, offhand, offhanded, off-the-cuff, snap, spur-of-the-moment, unconsidered, unplanned, unpremeditated, unprepared, unprompted, unreasoned, unrehearsed, unstudied; casual, chance, chancy, haphazard, hasty, hit-or-miss, impetuous, impulsive, mindless, random, rash
Near Antonyms
calculated, conscious, cultivated, deliberate, designed, intended, intentional, predetermined, prepared, projected, refined, rehearsed, volitional, voluntary, willed, willful (or wilful); advised, aforethought, careful, considered, foresighted, forethoughtful, measured, meticulous, reasoned, studied, thoughtful

knee jerk

noun

Definition of knee jerk

:an involuntary forward kick produced by a light blow on the tendon below the patella

See knee jerk defined for kids

First Known Use of knee jerk

1876

KNEE-JERK Defined for English Language Learners

knee-jerk

adjective

Definition of knee-jerk for English Language Learners

  • : occurring quickly and without thought

  • : often reacting quickly and without thought

Medical Dictionary

knee jerk

noun

medical Definition of knee jerk

:an involuntary forward jerk or kick produced by a light blow or sudden strain upon the patellar tendon of the knee that causes a reflex contraction of the quadriceps muscle — called also patellar reflex

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  1. See words that rhyme with knee-jerk Thesaurus: All synonyms and antonyms for knee-jerk

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