Definition of nightmare
1 : an evil spirit formerly thought to oppress people during sleep
2 : a frightening dream that usually awakens the sleeper
3 : something (such as an experience, situation, or object) having the monstrous character of a nightmare or producing a feeling of anxiety or terror
nightmarishplay \ˈnīt-ˌmer-ish\ adjective
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Examples of nightmare in a Sentence
Mommy, I had a really scary nightmare.
The party was a complete nightmare.
Recent Examples of nightmare from the Web
The weeks of investigation ahead will be a national nightmare, because Donald Trump won't keep his mouth shut.
Brandt, with shrapnel under his skin and nightmares in his head, has too.
Beckham still must seek approvals by the city of Miami to build the stadium, a process sure to involve fighting the nearby Spring Garden neighborhood, where residents have warned of a traffic nightmare from a sports venue without garages.
That nightmare scenario came to pass Tuesday morning for a 24-year-old Canadian truck driver who struck a bridge, then got stuck under it, in Tonawanda, N.Y.
For the octopus, with thousands of suckers studding symmetric arms, each of which can bend at any point, building a central mental representation of how to move seems like a computational nightmare.
That’s a nightmare scenario, with grim ramifications for the country going forward.
What was supposed to be a cost-saving measure soon turned into a nightmare for residents.
So if spending time without your air conditioner sounds like a nightmare, this may not be for you. ...
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'nightmare'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Did You Know?
Looking at nightmare, you might guess that it is a compound formed from night and mare. If so, your guess is correct. But while the night in nightmare makes sense, the mare part is less obvious. Most English speakers know mare as a word for a female horse or similar equine animal, but the mare of nightmare is a different word, an obsolete one referring to an evil spirit that was once thought to produce feelings of suffocation in people while they slept. By the 14th century the mare was also known as a nightmare, and by the late 16th century nightmare was also being applied to the feelings of distress caused by the spirit, and then to frightening or unpleasant dreams.
Origin and Etymology of nightmare
Middle English, from 1night + 1mare
First Known Use: 14th century
NIGHTMARE Defined for English Language Learners
Definition of nightmare for English Language Learners
: a dream that frightens a sleeping person : a very bad dream
: a very bad or frightening experience or situation
NIGHTMARE Defined for Kids
Definition of nightmare for Students
1 : a frightening dream
2 : a horrible experience
History for nightmare
The -mare in nightmare comes from an Old English word for a kind of evil spirit. Such spirits were believed to bother people who were sleeping.
Medical Definition of nightmare
: a frightening or distressing dream that usually awakens the sleeper
Learn More about nightmare
See words that rhyme with nightmare Thesaurus: All synonyms and antonyms for nightmare Spanish Central: Translation of nightmare Nglish: Translation of nightmare for Spanish speakers Britannica English: Translation of nightmare for Arabic speakers Britannica.com: Encyclopedia article about nightmare
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