\ ˈnē-ˌjərk How to pronounce knee-jerk (audio) , -ˈjərk\

Definition of knee-jerk

 (Entry 1 of 2)

: readily predictable : automatic knee-jerk reactions also, disapproving : reacting in a readily predictable way The man was such a bleeding-heart knee-jerk liberal that you could predict the rest of the column after reading the first sentence. — Andrew M. Greeley

knee jerk


Definition of knee jerk (Entry 2 of 2)

: an involuntary forward kick produced by a light blow on the tendon below the patella

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Synonyms & Antonyms for knee-jerk

Synonyms: Adjective

automatic, instinctive, instinctual, involuntary, mechanic, mechanical, robotic, spontaneous

Antonyms: Adjective


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Examples of knee-jerk in a Sentence

Recent Examples on the Web: Noun

The fact that our knee jerk reaction to a woman becoming single is one of exhilarated empowerment rather than pity or dismay shows that minds have been changed, even slightly. Kathryn Lindsay,, "Why Be Engaged When You Can Be An Ex?," 13 July 2018 But the narrative that opposition to the reconstruction is being driven only by an overblown reverence for Bill Bowerman and Steve Prefontaine is knee jerk and, wrong., "Comment about opponents of Hayward reconstruction is unfair: Oregon track & field rundown," 29 Apr. 2018 Shouldn’t have gone against Americans with your knee jerk pandering to the gun grabbers. Alex Leary And Steve Bousquet, miamiherald, "Rick Scott ticked off the NRA after Parkland. That could help him. | Miami Herald," 13 Apr. 2018 Trump and his trade team’s knee jerk reaction appears to be a tariff. Christine Mcdaniel, Fortune, "Commentary: Tariffs Are the Wrong Way to Punish China for Stealing Our Technology," 22 Mar. 2018 Part of our problem in this country is media hype and knee jerk reactions — vickey (@fvr510) January 18, 2018 Excellent. Max Londberg, kansascity, "Trump moves to protect health care workers’ religious rights to refuse patients," 18 Jan. 2018 Nakano said any knee jerk reaction to the North Korean threat could risk inflaming tensions across the region. Ben Westcott, CNN, "Japan split over how to deal with North Korean missile launches," 15 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'knee-jerk.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of knee-jerk


1958, in the meaning defined above


1849, in the meaning defined above

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Time Traveler for knee-jerk

The first known use of knee-jerk was in 1849

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More Definitions for knee-jerk



English Language Learners Definition of knee-jerk

: occurring quickly and without thought
disapproving : often reacting quickly and without thought

knee jerk


Medical Definition of knee jerk

: an involuntary forward jerk or kick produced by a light blow or sudden strain upon the patellar tendon of the knee that causes a reflex contraction of the quadriceps muscle

called also patellar reflex

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miscellaneous remnants or debris

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