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Synonyms

frightful

American  
[frahyt-fuhl] / ˈfraɪt fəl /

adjective

  1. such as to cause fright; dreadful, terrible, or alarming.

    A frightful howl woke us.
    Synonyms:
    awful, fearful
    Antonyms:
    delightful

  2. horrible, shocking, or revolting.

    The storm did frightful damage.
    Synonyms:
    gruesome, ghastly, horrid, dread, hideous
    Antonyms:
    delightful

  3. Informal. unpleasant; disagreeable.

    We had a frightful time.

  4. Informal. very great; extreme.

    That actor is very talented but a frightful ham.
frightful British  
/ ˈfraɪtfʊl /

adjective

  1. very alarming, distressing, or horrifying

  2. unpleasant, annoying, or extreme

    a frightful hurry
"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

Other Word Forms

  • frightfully adverb
  • frightfulness noun
  • unfrightful adjective

Etymology

Origin of frightful

Middle English word dating back to 1200–50; fright, -ful

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.

Even before DOGE, Musk had a frightful habit of posting online, often tweeting 100 times a day.

From Salon • May 30, 2025

Walker said the conditions for such a catch are frightful.

From Los Angeles Times • Sep. 1, 2024

It’s a frightful and gargantuan performance that should come with a trigger warning.

From New York Times • Feb. 29, 2024

Yes, people may have tips and comfort to share, but they also offer a frightful peek into the future.

From Slate • Jan. 28, 2024

There are times when something is so frightful you become mesmerised by it and can't look away.

From "The Witches" by Roald Dahl

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.