Insomnia definition

ĭn-sŏmnē-ə

Insomnia is defined as an ongoing inability to sleep or stay asleep.

When you have trouble falling asleep even though you are tired, this is an example of insomnia.

noun

Chronic inability to fall asleep or remain asleep for an adequate length of time.

noun

Chronic inability to fall asleep or remain asleep for an adequate length of time.

noun

Chronic inability to fall asleep or remain asleep for an adequate length of time.

A sleeping disorder that is known for its symptoms of unrest and the inability to sleep.

noun

Abnormally prolonged inability to sleep, esp. when chronic.

noun

Other Word Forms

Singular:

insomnia

Plural:

insomnias

Latin īnsomnia from īnsomnis sleepless in- not in–¹ somnus sleep swep- in Indo-European roots

From American Heritage Dictionary of the English Language, 5th Edition
From Latin in- (“without”) +‎ somnus (“sleep”) +‎ -ia.

From Wiktionary