Where does “nightmare” come from?

Nightmare comes from Middle English nightmare, from Old English nihtmare, from Proto-West Germanic nahtmarā, combining naht (night) and a root related to Proto-Indo-European mor- or mer- (to harm or frighten).

nightmare (English): A demon or monster, thought to plague people...

Definitions

  1. A demon or monster, thought to plague people...

Ancestry of “nightmare”, step by step

nightmare traces back through 3 separate lines of ancestry.

via English night

StepLanguageWordMeaning
1EnglishnightThe period between sunset and sunrise, when a...
2Middle EnglishnyghtAlternative form of nighte; Alternative form of...
3Middle Englishnightenight
4Old EnglishnyhtAlternative form of niht
5Proto-West Germanicnahtnight
6Proto-Germanicnahtsnight
7Proto-Indo-Europeannókʷtsnight
8Proto-Indo-Europeannegʷ-bare, naked

via English Maré

StepLanguageWordMeaning
1EnglishMaréAn adult female horse
2Middle EnglishmareA horse member of the species
3Old Englishmaremare (evil spirit thought to torment people in their sleep)
4Proto-West Germanicmarāevil spirit, nightmare
5Proto-Germanicmarǭevil spirit; succubus; incubus; nightmare
6Proto-Indo-Europeanmor-to blacken, to dirty; dirt spot; to rub, pound,...
7Proto-Indo-Europeanmer-to die; to disappear; sea, lake, wetland

via Middle English nyghtmare

StepLanguageWordMeaning
1Middle EnglishnyghtmareAn evil spirit attacking men or horses at night
2Old Englishnihtmaremare; nightmare
3Proto-West Germanicnahtmarānightmare

Words derived from “nightmare

Every word from Proto-Indo-European negʷ-
nightmare — Etymology, Origin & Word History | Etymology Explorer