insomnia

in-SOM-nee-uh /ɪnˈsɒmniə/
nounB2IELTSTOEFLUPSC
neutralmedical

Habitual sleeplessness; the inability to fall asleep or stay asleep for an adequate duration.

Insomnia can refer to a temporary, situational struggle to sleep or a chronic medical condition diagnosed by a physician.

The story behind the word. Formed in the early 17th century from the Latin prefix 'in-' (meaning 'not' or 'without') and 'somnus' (meaning 'sleep'). It literally translates to 'no-sleep'. The suffix '-ia' denotes a pathological condition or state.

Word relationships

  • sleeplessness: 'Sleeplessness' is a simpler, Anglo-Saxon term, whereas 'insomnia' is the formal, medical term.
  • somnolence: 'Somnolence' is the state of drowsiness or strong desire to sleep, the opposite of being unable to sleep.

Commonly confused with

  • sleep deprivation: 'Sleep deprivation' is the lack of sleep due to external constraints (like a crying baby or long work hours), whereas 'insomnia' is the internal biological inability to sleep.

Word family

  • insomniac (noun): A person who regularly suffers from insomnia.
  • insomnious (adjective): Sleepless; suffering from insomnia.

Collocations

  • suffer from insomnia
  • chronic insomnia
  • insomnia cure

Example sentences

  • "Stress at work is one of the leading causes of temporary insomnia among young adults." Discussing the modern epidemic of sleep issues.
  • "He suffered from chronic insomnia, often spending his nights pacing the floor of his study." From a famous psychological profile.

Memory hook

Think of 'IN' (not) + 'SOMNIA' (dreams/sleep). If you are 'in insomnia', you are locked out of the world of dreams. In-somnia: Inside, you are wishing for somnia (sleep).

When not to use

Do not use 'insomnia' to describe simply staying up late voluntarily (e.g., to study or party); it must involve an inability to sleep despite wanting to.

Fun facts

  • The word 'somnambulism' (sleepwalking) shares the same root 'somnus', combined with 'ambulare' (to walk).
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