insomnia
Americannoun
-
insomnias
plural
noun
Usage
What does insomnia mean? Insomnia is the inability to fall asleep or stay asleep for an adequate amount of time. Insomnia is often used casually to refer to occasional sleeplessness or a single instance of it. But in medical terms, insomnia typically refers to a condition involving a chronic inability to fall or stay asleep, meaning the inability is persistent and prolonged—it happens all the time. A person who experiences insomnia can be called an insomniac. Example: My insomnia gets worse when I’m under a lot of stress.
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of insomnia
First recorded in 1685–95; from Latin, equivalent to insomn(is) “sleepless” ( in- in- 3 + somn(us) “sleep” + -is, adjective suffix) + -ia -ia
Explanation
A person who has trouble falling or staying asleep is suffering from insomnia. If after a hot bath, a glass of warm milk, and hours of counting sheep, you still find yourself lying wide awake in bed, it's time to admit you have insomnia. There's no cure for insomnia, but people with insomnia are advised to go to bed at the same time every night and to try to avoid stress. The noun insomnia was borrowed from Latin insomnis "sleepless," from the prefix in-, "not," plus somnus, "sleep." Somnus is actually related to Greek hypnos "sleep," the source of English words such as hypnosis and hypnotic.
Vocabulary lists containing insomnia
Psychological Conditions and Disorders
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Psychology
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Vocabulary Video Contest (2013) - List 1
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
In a small study on people with insomnia, when they were given a false negative sleep score, those individuals reported sleepiness and fatigue, as well as lower levels of alertness and clear thinking.
From Slate ● Aug. 11, 2026
"My parents blame me. I have insomnia and anxiety. I can't focus on work."
From BBC ● Aug. 10, 2026
Taylor-Joy, who splits time between London and Los Angeles with her American musician husband, Malcolm McRae, talked about overcoming insomnia, greeting gorillas and meditating.
From The Wall Street Journal ● Aug. 3, 2026
She also suffered an intense fear of men, uncontrollable crying spells and insomnia.
From Los Angeles Times ● Aug. 1, 2026
Long after midnight; but his insomnia had not been fruitless; he had a plan.
From "Brave New World" by Aldous Huxley
He contemplated the black immensity pierced by a multitude of lights, without giving a thought to all the heavy slumbers, cruel insomnias, vain dreams, spoilt pleasures, and infinitely diverse miseries that a great city contains.
From Penguin Island by Anatole France
They prattled of the dietary and idiosyncrasies of their several insomnias as though they had been so many exacting pet animals.
From Punch, or the London Charivari, Vol. 158, 1920-02-18 by Various
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
