A knee-jerk cynic.
He gave a knee-jerk response.
The earliest-studied of these, the "knee-jerk," may serve as example of the class.
knee jerkthat there is a clear rejection of the knee-jerk anti-Americanism that's impossible to escape in daily life.
But the response from the alternative crowd wasn't a knee-jerk reaction.
A little experience in observations on the knee-jerk imparts a notion of the average strength of the "jerk."
The muscles become less tense than in their waking state: their tonus is diminished, the upper eyelid falls, and the knee-jerk is in abeyance.