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Synonyms

nightmarish

American  
[nahyt-mair-ish] / ˈnaɪtˌmɛər ɪʃ /

adjective

  1. resembling a nightmare, especially in being terrifying, exasperating, or the like.

    his nightmarish experience in a concentration camp.


Other Word Forms

Etymology

Origin of nightmarish

First recorded in 1825–35; nightmare + -ish 1

Explanation

Something nightmarish is truly horrifying, something that would show up in a bad dream. Your nightmarish day might start with a car accident on the way to school and end with a fight with your best friend. A chilling scream in the middle of the night is nightmarish, and traumatic experiences like an episode of bullying or nearly stumbling off the top of a cliff would also be nightmarish. You can also use this adjective to emphasize the unpleasantness of an experience in a slightly exaggerated way: "Ugh, that math test was absolutely nightmarish." Nightmarish things resemble nightmares, or terrifying dreams.

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Vocabulary lists containing nightmarish

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

At around age 19 or 20, he began having regular night terrors and daily flashbacks to “horrific, nightmarish things.”

From Slate Sep. 22, 2026

Fifth last season was reasonable, but it must have felt nightmarish to Hibs fans as Hearts roared on and threatened to win the league.

From BBC Sep. 16, 2026

Our critic called the presentation “an uneasy and vivid blend of daydream and nightmarish reality.”

From The Wall Street Journal Aug. 16, 2026

One of its all-time best, Season 2’s “Teddy Perkins,” contained all the tension of a nightmarish horror thriller.

From Salon Jul. 1, 2026

They were all shuffling through a maze of guide ropes, like weary overgrown children at some nightmarish amusement park.

From "Ready Player One: A Novel" by Ernest Cline

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