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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

  • nightmarishly adverb
  • nightmarishness noun

Etymology

Origin of nightmarish

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

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

South Korean stocks extended their recent nightmarish run on Monday after oil topped $100 a barrel for the first time since the aftermath of Russia invading Ukraine.

From Barron's • Mar. 9, 2026

Harvey Pratt was a young police officer in Midwest City, Okla., during a string of nightmarish murders in the early 1960s.

From The Wall Street Journal • Jan. 29, 2026

The soaking rains may threaten coastal cities with flash floods and nightmarish traffic, but they promise sweet relief for snow-starved thrill seekers from Lake Tahoe to the San Bernardino Mountains in Southern California.

From Los Angeles Times • Dec. 22, 2025

The colors were nightmarish, the lines jagged, the images disturbing.

From "Zeitoun" by Dave Eggers