nightmare

noun
night·​mare | \ ˈnīt-ˌmer \

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 \ 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

Watching Nancy Pelosi become Donald Trump’s worst nightmare is a delight! Molly Jong-fast, Glamour, "We’ve Outgrown the Women’s March. Here’s What Happens Next.," 18 Jan. 2019 Because for a mother to go through that is a true nightmare. Gaby Wood, Marie Claire, "Penélope Cruz Isn't Scared to Look Back," 4 Jan. 2019 In a six-part story for The Los Angeles Times and the accompanying podcast Dirty John, reporter Christopher Goffard chronicles how Debra's dream guy became a waking nightmare for her and her family. Emma Dibdin, Harper's BAZAAR, "A Complete Timeline of the Events of Dirty John," 14 Jan. 2019 That could become a nightmare—particularly for smaller biotechs that generally burn cash and need a predictable regulatory process to function properly. Charley Grant, WSJ, "Would Big Pharma Pay for the Wall?," 12 Jan. 2019 Alaska Airlines faced a furious reaction from outraged passengers Monday following a weekend transcontinental flight that turned into a 30-hour nightmare journey. Dominic Gates, The Seattle Times, "Alaska Airlines flight diversion leads to a 30-hour nightmare for passengers," 8 Jan. 2019 The versatile protein is both a dream and a nightmare. Audrey Bruno, SELF, "All the Different Ways to Thaw Chicken Breasts, Ranked," 5 Jan. 2019 Shipping large items, like furniture, is a logistical nightmare. Diana Budds, Curbed, "The rise of the direct-to-consumer home," 21 Dec. 2018 Directed by James Wan — the master of high-octane nightmare fuel like Insidious, The Conjuring and Saw — Aquaman contains moments of pure joy, stylish fight-sequence hairography, and unabashed fidelity to cheese and fantasy. Alex Abad-santos, Vox, "Aquaman goes for broke and lands somewhere between overstuffed marine opera and cheesy comic book fun," 11 Dec. 2018

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

3 Feb 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 \

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 \

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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