Patellar reflex

from WordNet (r) 3.0 (2006)

patellar reflex
    n 1: a reflex extension of the leg resulting from a sharp tap on
         the patellar tendon [syn: {knee jerk}, {knee-jerk reflex},
         {patellar reflex}]

from The Collaborative International Dictionary of English v.0.48

Reflex \Re"flex\ (r?"fl?ks; formerly r?*fl?ks"), n. [L. reflexus
   a bending back. See {Reflect}.]
   1. Reflection; the light reflected from an illuminated
      surface to one in shade.
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            Yon gray is not the morning's eye,
            'Tis but the pale reflex of Cynthia's brow. --Shak.
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            On the depths of death there swims
            The reflex of a human face.           --Tennyson.
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   2. (Physiol.) An involuntary movement produced by reflex
      action.
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   {Patellar reflex}. See {Knee jerk}, under {Knee}.
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