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 in the past fortnight the Georgian Dream has turned into a nightmare. The Economist, "Russia plays games with Georgia," 6 July 2019 By reportedly encouraging his father-in-law to fire James Comey, Jared also helped transform the Russia investigation into a two-year political nightmare for the president. Matt Ford, The New Republic, "The Kids Aren’t Alright," 3 July 2019 And, since smart home gadgets have in some instances been the stuff of privacy nightmares, Apple is attempting to make the smart home ... smarter. Lauren Goode, WIRED, "An iOS 13 Preview: The 7 Top Features Coming to Your iPhone," 25 June 2019 Here are his tips make sure that dream doesn't turn into a nightmare. Melissa Yeager, azcentral, "Booking a trip? 'Hotel Impossible' star gives tips on how to avoid travel nightmares," 13 June 2019 The bullpen day that began so promisingly had ended in a nightmare. San Diego Union-Tribune, "Four! Nats history torpedos Padres’ bullpen day," 9 June 2019 That’s enough to give anyone holiday season nightmares. Jessica Macleish, Teen Vogue, "10 Details in "Chilling Adventures of Sabrina: A Midwinter’s Tale" You Might Have Missed," 14 Dec. 2018 The Pelicans have the best defensive backcourt in the Western Conference, if not the entire NBA. Ingram and Williamson are interchangeable matchup nightmares on the offensive end. Jeff Duncan, nola.com, "Anthony Davis trade creates endless possibilities, bright future for Pelicans," 16 June 2019 Trigger-happy The trouble is that reconfiguring conglomerates can be a nightmare. The Economist, "The UTC-Raytheon deal highlights the changing nature of war," 14 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

7 Jul 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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