nightmarish
Americanadjective
Other Word Forms
Etymology
Origin of nightmarish
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.
Vocabulary lists containing nightmarish
Rowan of Rin
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Novel Study: Their Eyes Were Watching God, Chapters 12–20
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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.
The attempt went relatively smoothly, she explains, apart from a "nightmarish" section when cleaning a kid's playground at four in the morning where the game's bright primary colours affected her in "a very psychedelic way".
From BBC • Apr. 3, 2026
By then, a dream start and 36-31 halftime lead, had settled into a nightmarish second half for USC.
From Los Angeles Times • Feb. 28, 2026
It also extended a nightmarish stretch of Olympic finishes in Shiffrin’s otherwise outstanding career.
From The Wall Street Journal • Feb. 10, 2026
The author also announced in the statement that he’s been working on a book throughout the “strange, turbulent and occasionally nightmarish year and a half.”
From Los Angeles Times • Feb. 2, 2026
The master had said it in so many words—my reward for whatever awaited me in this nightmarish new world into which I had enlisted.
From "Flying Through Water" by Mamle Wolo
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.