knee-jerk

adjective

ˈnē-ˌjərk How to pronounce knee-jerk (audio)
Definition of knee-jerknext
as in automatic
done instantly and without conscious thought or decision a colleague known for her knee-jerk rejection of any proposal that she didn't originate

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of knee-jerk After a knee-jerk reaction to the downside, stocks stateside look set to recover some of those losses on Thursday, with a broadly positive handover from global equities. — Leonie Kidd, CNBC, 17 Sep. 2026 Part of it is simply a knee-jerk reaction that companies may display in the face of a new technology that might undermine their control. — Jeff John Roberts, Fortune, 14 Sep. 2026 Season openers often produce outlier performances and knee-jerk overreactions that look like complete mirages by the end of the year. — Antwan Staley, New York Daily News, 14 Sep. 2026 My knee-jerk is to recoil from anything that brings AI close to Baldwin’s work. — James Folta, Literary Hub, 14 Sep. 2026 See All Example Sentences for knee-jerk
Recent Examples of Synonyms for knee-jerk
  1. automatic
  2. reflex
  3. mechanical
  4. spontaneous
  5. instinctive
  6. robotic
  7. sudden
  8. mechanic
Adjective
  • Non-metallic shells insulate metallic components, conductive feet provide grounding, and automatic cutoffs monitor temperature.
    — Prabhat Ranjan Mishra, Interesting Engineering, 30 Oct. 2026
  • The Sacramento County District Attorney’s Office charged Hernandez Santana, 65, with firing a gun into an inhabited building, assault with a semi-automatic firearm and firing a gun in a grossly negligent manner.
    — Rosalio Ahumada, Sacbee.com, 29 Oct. 2026
Definition of automatic
Adjective
  • The reflex sell-off after Wednesday's Federal Reserve rate hike gave the S&P 500 a momentary test of 7500, which proved a timely shakeout.
    — Michael Santoli, CNBC, 22 Sep. 2026
  • Padmini smiled, though this appeared more reflex than friendliness.
    — Madhuri Vijay, New Yorker, 16 Aug. 2026
Definition of reflex
Adjective
  • No mechanical failure, operational error, or other contributing factor has been identified.
    — Neetika Walter, Interesting Engineering, 30 Oct. 2026
  • Yao also thinks that there may be more promising sources of energy to harvest from than mechanical motion, which requires implantation in parts of the body where motion is constant.
    — Edd Gent, IEEE Spectrum, 29 Oct. 2026
Definition of mechanical
Adjective
  • Much like her character Klara, Ortega chooses to have faith in humans and their spontaneous wonder.
    — Andrea Flores, Los Angeles Times, 22 Oct. 2026
  • Celine’s Michael Rider leads a pack of creatives who seek spontaneous styling, embrace imperfection, and refuse to be bound by rules.
    — Laird Borrelli-Persson, Vogue, 21 Oct. 2026
Definition of spontaneous
Adjective
  • Like Irving Berlin, Miranda is an instinctive musician whose mistakes can be worth more than other people’s rules.
    — Adam Gopnik, New Yorker, 26 Oct. 2026
  • Cinema needs women who are complicated, instinctive, ambitious, vulnerable, fearless and free – women who do not ask permission to take up space.
    — Leo Barraclough, Variety, 20 Oct. 2026
Definition of instinctive
Adjective
  • Electrodes placed on the skin detect these signals, which software then translates into commands for a robotic limb.
    — Kaif Shaikh, Interesting Engineering, 29 Oct. 2026
  • Olivas himself hung off the end of Atlantis’ robotic arm (the Endeavour has one too) to close a 4-inch hole in the heat-shielding thermal blanket with a medical stapler (the flight surgeon’s idea).
    — Laura Zornosa, Los Angeles Times, 28 Oct. 2026
Definition of robotic
Adjective
  • Lucy leaves their countryside home with Johnny immediately, going straight to her mother’s house ( Catherine Deneuve plays mom), but avoids telling her, or anyone else, the specifics of this sudden separation.
    — ABC News, ABC News, 28 Oct. 2026
  • All of a sudden, the war took on a more present form, unsettling a kingdom unused to conflicts playing out on home turf.
    — Nabih Bulos, Los Angeles Times, 28 Oct. 2026
Definition of sudden
Adjective
  • Parched fields force hydroponic growers, vegetable farmers and fruit producers to halt harvests, sell off underfed livestock at rock-bottom prices and even return to mechanic jobs to survive.
    — Dánica Coto, Los Angeles Times, 26 Aug. 2026
  • There are exceptions and one is Hig (Elordi), who before the virus hit was a mechanic living a good life with his pregnant wife and new puppy.
    — Pete Hammond, Deadline, 25 Aug. 2026
Definition of mechanic

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knee-jerk
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Cite this Entry

“Knee-jerk.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/knee-jerk. Accessed 30 Oct. 2026.

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