nightmare (English)

Where does "nightmare" come from?

The word 'nightmare' is a compound of the Old English words 'niht' (night) and 'mare,' the latter referring to an evil spirit in Germanic folklore believed to afflict sleeping people. This 'mare' traces back to a Proto-Indo-European root associated with death, eventually evolving from its literal meaning of a suffocating demon into our modern term for a frightening dream or deeply distressing situation. Through various Germanic branches, including Middle Low German and Dutch, the term maintained its dark association with nocturnal terror before being adopted into English.

Full etymology tree

nightmare (English), 'A very unpleasant or frightening dream.'
- inherited night-mare (Middle English), 'An evil spirit attacking men or horses at night.'
  - inherited *nihtmare (Old English), 'mare (evil spirit thought to torment people in their sleep)'
    - compound niht (Old English), 'night'
      - inherited *nahti (Proto-West Germanic)
        inherited *nahts (Proto-Germanic), 'night'
        inherited *nókʷts (Proto-Indo-European), 'night (or possibly 'evening')'
    - compound mare (Old English), 'mare (evil spirit thought to torment people in their sleep)'
      - inherited *marā (Proto-West Germanic), 'evil spirit, nightmare'
        inherited *marǭ (Proto-Germanic), 'nightmare'
        inherited *mor- (Proto-Indo-European)
        inherited *mer- (Proto-Indo-European), 'to die'

Direct ancestors

Updated July 2026

Etymology data from Wiktionary, CC BY-SA 4.0 · About Miraris