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

On days when exercise is at the bottom of your priority list and making it to a fitness class on time presents a scheduling nightmare, a HIIT workout can be your saving grace. Amy Marturana, SELF, "A 10-Minute Total-Body Dumbbell HIIT Workout You Can Do on Busy Days," 9 May 2019 In 2017, the family of three became stars of a new show, Nate & Jeremiah by Design, in which the designer couple help homeowners solve nightmare renovations—all while juggling parenthood. Hadley Keller, House Beautiful, "A Brief Timeline of Nate Berkus & Jeremiah Brent's Relationship," 3 May 2019 Johnson had 68 catches for 985 yards and his size makes him a matchup nightmare for Big 12 cornerbacks. Jim Vertuno, The Seattle Times, "After 10-4 finish, Longhorns have to plug up defense," 13 Apr. 2019 As ProPublica reports, a bipartisan bill coming out of the House Ways & Means Committee aims to ensure that filing your taxes remains a confusing and potentially expensive nightmare. Eric Limer, Popular Mechanics, "Politicians and Tax Prep Companies Are Teaming Up to Make Sure Filing Stays an Expensive Nightmare," 9 Apr. 2019 Here’s what to know about the couple who lived out this terrifying public nightmare. Megan Stein, Country Living, "Who Are Madeleine McCann's Parents? What to Know About Kate and Gerry McCann," 14 Mar. 2019 Dogs can be trained to immediately wake owners who have been suffering from a nightmare, which, according to the report, no medication has been able to do before. Elizabeth Gulino, House Beautiful, "Having a Dog Can Help You Sleep Better, According to Science," 12 Apr. 2019 Somehow, those thin rubber straps always get tangled and knotted up in your hair, which can be a nightmare when little ones are involved. Shanon Maglente, Good Housekeeping, "These Goggles Won't Pull Your Hair — and They are Selling Out FAST," 20 Mar. 2019 Whether a cashless consumer experience is your idea of heaven or a dystopian nightmare, a case against paper money is easy to make. Town & Country, "Is This the End of Cash?," 28 Jan. 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

12 May 2019

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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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