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
Cite this Entry
“Insomnia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/insomnia. Accessed 4 Sep. 2026.
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