knee-jerk

adjective \ ˈnē-ˌjərk , -ˈjərk \

Definition of knee-jerk

:readily predictable :automatic
  • knee-jerk reactions
; alsodisapproving :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

knee jerk

noun

Definition of knee jerk

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

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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