What does insomniac mean?
An insomniac is a person who cannot sleep easily or remain asleep for long enough to feel rested. The condition itself is called insomnia, but insomniac focuses on the sufferer rather than the medical condition. It can be used literally, as in a person who regularly lies awake at night, or more figuratively, for someone whose thoughts, anxiety, or restless imagination keeps them from sleeping. The word often carries a sympathetic but slightly literary tone, and it may suggest a problem that is persistent or difficult to resolve. In contemporary usage, sleep difficulties are also described with terms such as sleeplessness, sleep disturbance, and difficulty sleeping, which may sound more clinical or less dramatic. An insomniac is especially familiar from personal accounts, literature, and discussions of chronic sleep problems.
A person who suffers from insomnia or has persistent difficulty sleeping.
"She had become an insomniac, spending many nights awake in silence."
Commonly used for someone whose sleep problems are recurrent or persistent; it can also be used figuratively.
Characterized by or affected by sleeplessness.
"He faced the morning with the anxious, insomniac expression of someone who had barely slept."
Less common than the noun and often used attributively or figuratively.
The standard plural of the noun is insomniacs.
"The insomniacs exchanged advice in an online support group."
The word insomniac turns sleeplessness into a person: while others are waiting for sleep, the insomniac is often the one still awake.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of insomniac
The word is formed from the Latin insomnia, meaning "sleeplessness," which is built from the prefix in- and somnus, Latin for "sleep." In English, insomnia was established before the related form insomniac, which adds the suffix -iac and came to mean a person prone to sleeplessness. The same Latin root also underlies words such as somnambulist, referring to a sleepwalker.
Related word forms
How insomniac is actually used
As a noun, insomniac is most common when referring to someone who repeatedly has difficulty sleeping. As an adjective, it is somewhat less frequent and is often used attributively, as in "an insomniac mind."
Easily confused with insomniac
Insomnia is the condition of being unable to sleep adequately, whereas an insomniac is a person who suffers from it.