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Synonyms

ominous

American  
[om-uh-nuhs] / ˈɒm ə nəs /

adjective

  1. An image of the word ominous as defined by portending evil or harm; foreboding; threatening; inauspicious.

    portending evil or harm; foreboding; threatening; inauspicious.

    an ominous bank of dark clouds.

  2. indicating the nature of a future event, for good or evil; having the significance of an omen; being a portent.

    Some of these events were immediately ominous, while others only later revealed themselves as such.


ominous British  
/ ˈɒmɪnəs /

adjective

  1. foreboding evil

  2. serving as or having significance as an omen

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Synonym Usage

Ominous, portentous, threatening, menacing, fateful are adjectives describing that which forebodes a serious, significant, and often harmful outcome. Ominous, derived from omen “a predictor of outcomes,” usually suggests evil or damaging eventualities: ominous storm clouds; an ominous silence. Portentous, although it may suggest evil results, often stresses a momentous or very important outcome: a portentous moment in history; a portentous escalation of hostilities. Threatening may suggest calamity or great harm but sometimes mere unpleasantness: a threatening rumble from the volcano; A threatening look from his brother caused him to quickly change the subject. Menacing always suggests serious damage as an outcome: He advanced with a menacing swagger. Fateful most often stresses the great or decisive importance of what it describes: a fateful encounter between two future leaders; a fateful day that changed our world.

Other Word Forms


Etymology

Origin of ominous

First recorded in 1580–90; from Latin ōminōsus “portentous,” equivalent to ōmin- (stem of ōmen ) + -ōsus; see origin at omen, -ous


Explanation

If something looks or sounds ominous, be careful: a threat or an unpleasant event is at hand. If you see an ominous frown on your boss's face, you're in trouble! Ominous, and the related word omen both come from the 16th century Latin word ōmen "foreboding." However, unlike omen, which is a sign of something good or bad to come, ominous always describes something unpleasant or threatening. If the future looks ominous, you've got nothing to look forward to. Figuratively, an ominous sky or ominous clouds promise rain or a storm.

Keep Reading on Vocabulary.com

Vocabulary lists containing ominous

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:

But museum directors and security firms agree the Louvre breach set an ominous precedent.

From The Wall Street Journal ● Oct. 15, 2026

I think people assume that the guy who created “The Twilight Zone” and was this really creepy, ominous host must have been this very dark and tormented person.

From Salon ● Oct. 10, 2026

From the opening title track, we get quiet-to-loud structures with ominous minor-key guitar strumming that explodes on choruses, becoming saturated with distortion.

From The Wall Street Journal ● Sep. 29, 2026

The Kansas City Chiefs gave another ominous sign that they were back in business with a 33-30 overtime win over the Indianapolis Colts.

From BBC ● Sep. 21, 2026

Another shiver of panic rattled through her body at the ominous words, and more questions darted through her mind.

From "Beasts of Prey" by Ayana Gray

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