cat·​a·​plexy | \ ˈka-tə-ˌplek-sē How to pronounce cataplexy (audio) \
plural cataplexies\ ˈka-​tə-​ˌplek-​sēz How to pronounce cataplexies (audio) \

Definition of cataplexy

: sudden loss of muscle power following a strong emotional stimulus

Examples of cataplexy in a Sentence

Recent Examples on the Web Then came the breakthrough: a litter of around seven Doberman puppies, all of them with narcolepsy and cataplexy. Henry Nicholls, CNN, "The science of sleep: Finding a cure for narcolepsy," 24 Oct. 2017 In 2007, Flygare, then a 24-year-old law student, was diagnosed with narcolepsy with cataplexy, a neurological disorder that causes chronic sleepiness and, in her case, symptoms of brief episodes of muscle weakness triggered by strong emotions. Maria Cartaya, CNN, "Runner: Having narcolepsy is harder than a marathon," 23 June 2017

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

First Known Use of cataplexy

1883, in the meaning defined above

History and Etymology for cataplexy

German Kataplexie, from Greek kataplēxis, from kataplēssein to strike down, terrify, from kata- + plēssein to strike — more at plaint

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Time Traveler for cataplexy

Time Traveler

The first known use of cataplexy was in 1883

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Cite this Entry

“Cataplexy.” Dictionary, Merriam-Webster, Accessed 8 Jul. 2020.

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More Definitions for cataplexy


cat·​a·​plexy | \ ˈkat-ə-ˌplek-sē How to pronounce cataplexy (audio) \
plural cataplexies\ -​sēz How to pronounce cataplexies (audio) \

Medical Definition of cataplexy

: a sudden loss of muscle control with retention of clear consciousness that follows a strong emotional stimulus (as elation, surprise, or anger) and is a characteristic symptom of narcolepsy

More from Merriam-Webster on cataplexy

Rhyming Dictionary: Words that rhyme with cataplexy Encyclopedia article about cataplexy

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