insomnia

noun

in·​som·​nia in-ˈsäm-nē-ə 

: prolonged and usually abnormal inability to get enough sleep especially due to trouble falling asleep or staying asleep

chronic insomnia

Insomnia is a patient-reported problem characterized by difficulty falling asleep or difficulty maintaining sleep; ie, frequent awakenings, difficulty returning to sleep after awakenings, or awakening too early with inability to return to sleep.

—Daniel J. Buysse

Synonyms

• sleeplessness
• wakefulness

Examples of insomnia in a Sentence

has suffered from insomnia virtually his entire life

Recent Examples on the Web

The list included anxiety, medical trauma, brain fog, insomnia, depression, menopause, grief, infertility, loneliness, fear of dying and more. —Vanessa Etienne, People.com, 24 Apr. 2025

Those effects can include headaches, insomnia, stomach upset, and vomiting. —Sean Mowbray, Discover Magazine, 22 Apr. 2025

Mayo Clinic said other symptoms of the disease are insomnia, blurry vision or blindness, and trouble swallowing. —Jonathan Limehouse, USA Today, 20 Apr. 2025

Additional causes of sleepiness Sleep disorders such as sleep apnea, insomnia, restless leg syndrome and circadian rhythm sleep disorders, as well as chronic pain conditions and medications can also contribute to sleepiness, which will be ruled out by a sleep specialist. —Sandee Lamotte, CNN Money, 14 Apr. 2025

Word History

Etymology

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

First Known Use

1739, in the meaning defined above

Kids Definition

insomnia

noun

in·​som·​nia in-ˈsäm-nē-ə 

: prolonged inability to sleep

Medical Definition

insomnia

noun

in·​som·​nia in-ˈsäm-nē-ə 

: prolonged and usually abnormal inability to obtain adequate sleep especially due to difficulty falling asleep or staying asleep

called also agrypnia