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

• restlessness
• wakefulness
• sleeplessness
• alertness

Examples of insomnia in a Sentence

has suffered from insomnia virtually his entire life

Recent Examples on the Web

With all that happening, the nation may have to grapple with more insomnia. —Brian Steinberg, Variety, 18 July 2025

This information could help providers tailor their recommendations to the sleep challenges of their individual patients with insomnia. —Kameryn Griesser, CNN Money, 17 July 2025

Kim Yates was experiencing anxiety and insomnia after having a stroke in November 2020, and her condition had worsened by April, according to court documents. —Bella Waters, Kansas City Star, 2 July 2025

Despite his busy schedule, the singer reportedly still struggled with insomnia. —Alex Gurley, People.com, 25 June 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