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knee jerk

noun

Definition of knee jerk

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



1876

First Known Use of knee jerk

1876


Medical Dictionary

knee jerk

noun

Medical Definition of knee jerk

  1. :  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




Learn More about knee jerk

  1. Medical Dictionary: Definition of knee jerk


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