Thesaurus.com Dictionary.com

involuntary impulse

NOUN

knee-jerk

Synonyms

WEAK

automatic response knee jerk reaction patellar reflex quadriceps reflex reflex

NOUN

knee-jerk reaction

Synonyms

WEAK

Pavlovian response absence of thought automatic reaction gut reaction

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.