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Synonyms

monstrous

American  
[mon-struhs] / ˈmɒn strəs /

adjective

  1. frightful or hideous, especially in appearance; extremely ugly.

    Synonyms:
    atrocious, horrible
  2. shocking or revolting; outrageous.

    monstrous cruelty.

    Synonyms:
    atrocious, horrible
  3. extraordinarily great; huge; immense.

    a monstrous building.

  4. deviating grotesquely from the natural or normal form or type.

  5. having the nature or appearance of a fabulous monster.


adverb

  1. extremely; exceedingly; very.

monstrous British  
/ ˈmɒnstrəs /

adjective

  1. abnormal, hideous, or unnatural in size, character, etc

  2. (of plants and animals) abnormal in structure

  3. outrageous, atrocious, or shocking

    it is monstrous how badly he is treated

  4. huge

    a monstrous fire

  5. of, relating to, or resembling a monster

"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

Related Words

See gigantic.

Other Word Forms

  • monstrously adverb
  • monstrousness noun

Etymology

Origin of monstrous

First recorded in 1350–1400; Middle English word from Latin word mōnstrōsus. See monster, -ous

Explanation

Monstrous is an adjective that describes something gross or shocking. It can refer to the size, shape, or general look of something. If your face or body is monstrous, it's misshapen and horrifying to look at. The word monstrous describes something that you'd like to avoid looking at, if at all possible. The word comes from the Latin monstruosus, which means "unnatural, deviating from the natural order, hideous." When discussing size, monstrous means that something or someone is so huge it's frightening. Monstrous can also describe someone or something that's extremely cruel or brutal, like a monstrous dictator or monstrous lies.

Keep Reading on Vocabulary.com

Vocabulary lists containing monstrous

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.

We know we are not monsters, but we are equally sure that we have done monstrous things.

From Slate • Mar. 16, 2026

The Russian foreign ministry described the strike as a "monstrous crime against the peaceful population".

From Barron's • Mar. 11, 2026

"I am outraged that this monstrous ballroom was designed and the construction of the original without any approval," another said.

From BBC • Mar. 5, 2026

After the movie came out, Lindo says, he met an incest survivor who said she appreciated the humanity he gave to a seemingly monstrous character.

From The Wall Street Journal • Mar. 3, 2026

Behind them were another dozen or so monstrous creatures, no two alike.

From "City of the Plague God" by Sarwat Chadda