Found 2 items, similar to knee jerk.
English → English (WordNet) Definition: knee jerk knee jerk n : a reflex extension of the leg resulting from a sharp tap on the patellar tendon [syn: knee-jerk reflex, patellar reflex ]
English → English (gcide) Definition: Knee jerk Knee jerk \Knee jerk\, n. emotional and predictable; -- of certain people and their reactions to events. [PJC] Knee jerk \Knee jerk\ (Physiol.) A jerk or forward kick of the lower part of the leg produced by a blow or sudden strain upon the patellar tendon of the knee, which causes a sudden contraction of the quadriceps muscle; the patellar reflex. [Webster 1913 Suppl.]