Word
knee-jerk reflex, n.
a reflex extension of the leg resulting from a sharp tap on the patellar tendon
<noun.act>
knee jerk
knee-jerk reflex
patellar reflex
semantic pointers
hypernym
reflex, reflex response, reflex action, instinctive reflex, innate reflex, inborn reflex, unconditioned reflex, physiological reaction