in·​som·​nia | \in-ˈsäm-nē-ə \

Definition of insomnia 

: prolonged and usually abnormal inability to get enough sleep

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Other Words from insomnia

insomniac \ in-​ˈsäm-​nē-​ˌak \ adjective or noun

Synonyms for insomnia


sleeplessness, wakefulness

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Examples of insomnia in a Sentence

has suffered from insomnia virtually his entire life

Recent Examples on the Web

The most common is headache, usually located at the back of the head and down the neck, but a wide variety of other symptoms can occur, ranging from weakness, fainting and difficulty swallowing to hearing loss, curvature of the spine and insomnia. Lisa Sanders, M.d., New York Times, "Why Was Her Vision Jerky and Blurry if There Was Nothing Wrong With Her Eyes?," 1 May 2018 Sleep = Happiness Stanford researchers found that resolving insomnia in depressed patients doubled the success rate of treating their depression. Adam Sternbergh, The Cut, "Read This Story and Get Happier," 28 May 2018 In other cases insomnia is a symptom of another medical condition (secondary insomnia). Carolyn L. Todd, SELF, "Charlize Theron Got Cannabis Edibles From Her Mom to Help Her Sleep," 12 Mar. 2018 That’s when insomnia propelled me to open randomly to Salzberg’s lines about generosity. Elizabeth Greenwood, Longreads, "The Month of Giving Dangerously," 31 Jan. 2018 Known as Wu Ling Shen, it traditionally was used to treat insomnia and help people recover from trauma (International Journal of Medicinal Mushrooms, Vol. Houston Chronicle, "Vicks VapoRub for poison ivy itch," 8 July 2018 Sitko and many others were given the drug, in part, to treat insomnia. Charles Piller, Science | AAAS, "Hidden conflicts? Pharma payments to FDA advisers after drug approvals spark ethical concerns," 5 July 2018 From massage oils to dog biscuits, a variety of products that purport to soothe ailments from insomnia to inflammation are available for sale in Illinois with little regulation. Vikki Ortiz,, "To calm dogs spooked by fireworks, pet owners are using treats made from marijuana plants," 3 July 2018 Doctors may be turning away from medication and headed toward more holistic methods to treat cancer survivors who suffer from severe insomnia. Lindsay Carlton, Fox News, "Acupuncture gives relief to cancer patients suffering insomnia," 8 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'insomnia.' 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 insomnia

circa 1623, in the meaning defined above

History and Etymology for insomnia

Latin, from insomnis sleepless, from in- + somnus sleep — more at somnolent

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Statistics for insomnia

Last Updated

12 Nov 2018

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Time Traveler for insomnia

The first known use of insomnia was circa 1623

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English Language Learners Definition of insomnia

: the condition of not being able to sleep


in·​som·​nia | \in-ˈsäm-nē-ə \

Kids Definition of insomnia

: difficulty in sleeping


in·​som·​nia | \in-ˈsäm-nē-ə \

Medical Definition of insomnia 

: prolonged and usually abnormal inability to obtain adequate sleep

called also agrypnia

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Comments on insomnia

What made you want to look up insomnia? Please tell us where you read or heard it (including the quote, if possible).


playful or foolish behavior

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