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

Other side effects can include erectile dysfunction, worsening symptoms in people with asthma, cold hands or feet, insomnia, and nightmares. —Aviel Kanter, Glamour, 10 Mar. 2025

Melatonin, a hormone regulating the sleep-wake cycle, is beneficial for short-term sleep issues like jet lag but lacks sufficient evidence for chronic insomnia treatment. —Lauryn Higgins, Flow Space, 10 Mar. 2025

It can also be used to treat insomnia that’s related to anxiety or temporary stressors. —Korin Miller, SELF, 3 Mar. 2025

The numbers made the Corby scandal the biggest child poisoning case since thalidomide, a drug that was marketed in the 1950s and '60s as a treatment for morning sickness and insomnia. —Lynsey Eidell, People.com, 28 Feb. 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