nightmare

noun
night·​mare | \ ˈnīt-ˌmer How to pronounce nightmare (audio) \

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

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Other Words from nightmare

nightmare adjective
nightmarish \ ˈnīt-​ˌmer-​ish How to pronounce nightmarish (audio) \ adjective
nightmarishly adverb

Synonyms & Antonyms for nightmare

Synonyms

agony, Gehenna, hell, horror, misery, murder, torment, torture

Antonyms

heaven, paradise

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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.

Examples of nightmare in a Sentence

Mommy, I had a really scary nightmare. The party was a complete nightmare.

Recent Examples on the Web

But reports of unrest have dominated the headlines in recent months, with Barça, as well as heavyweight rivals Real Madrid, linked with rescuing Neymar from his Parisian nightmare, albeit at huge financial cost. SI.com, "Barcelona 'Accelerate' Neymar Transfer Plans With Philippe Coutinho in Mix for PSG Switch," 11 Aug. 2019 Seven young outcasts are about to face their worst nightmare -- an ancient, shape-shifting evil that emerges every 27 years to prey on children. Los Angeles Times, "Here are the feature and TV films airing the week of Sunday, Aug. 11, 2019," 11 Aug. 2019 Mandy Buxrude's Pennywise costume will certainly be in our nightmares for the next month. Emily Sabens, Indianapolis Star, "Santa Claus, Chewbacca, creepy clowns and more: 21 of the best costumes we saw at Gen Con," 3 Aug. 2019 Usually, the handsome, debonair actor Idris Elba plays the man of our of dreams, though in the latest installment, or rather, spinoff of the Fast & Furious franchise, Hobbs & Shaw, Elba plays the man of our nightmares (but still somehow our dreams). Danielle Young, Essence, "Idris Elba Is The Most Delicious Villain You've Ever Seen In "Hobbs & Shaw"," 2 Aug. 2019 What one person considers sublime will be too hot for another person; my dream may be your cleansing nightmare. Allure Staff, Allure, "The Ultimate Bath Time Routine," 27 July 2019 The diagnosis was his worst nightmare — stage 4 cancer. Madeline Mcgee, Anchorage Daily News, "‘No time to wait’: After unprecedented cancer recovery, Wasilla man plans to make the most of the time he’s been given," 15 July 2019 The entire song is a neurotic envisioning of his worst nightmare: his lover straying. Elena Nicolaou, refinery29.com, "The Most Achy-Breaky Songs About Cheating," 5 July 2019 Renata faces two of her worst nightmares at the same time, one of which—naturally—concerns the wellbeing of Amabella. Sophie Gilbert, The Atlantic, "The Family Values of Big Little Lies," 7 June 2019

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.

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First Known Use of nightmare

14th century, in the meaning defined at sense 1

History and Etymology for nightmare

Middle English nyghte mare, from nyghte night entry 1 + mare mare entry 3

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Statistics for nightmare

Last Updated

18 Aug 2019

Look-up Popularity

Time Traveler for nightmare

The first known use of nightmare was in the 14th century

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More Definitions for nightmare

nightmare

noun

English Language Learners Definition of nightmare

: a dream that frightens a sleeping person : a very bad dream
: a very bad or frightening experience or situation

nightmare

noun
night·​mare | \ ˈnīt-ˌmer How to pronounce nightmare (audio) \

Kids Definition of nightmare

1 : a frightening dream
2 : a horrible experience

Other Words from nightmare

nightmarish \ ˈnīt-​ˌmer-​ish \ adjective

nightmare

noun
night·​mare | \ ˈnīt-ˌma(ə)r, -ˌme(ə)r How to pronounce nightmare (audio) \

Medical Definition of nightmare

: a frightening or distressing dream that usually awakens the sleeper

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Comments on nightmare

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