Dictionary.com
Thesaurus.com
Synonyms

diabolical

American  
[dahy-uh-bol-i-kuhl] / ˌdaɪ əˈbɒl ɪ kəl /
Also diabolic

adjective

  1. having the qualities of a devil; devilish; fiendish; outrageously wicked.

    a diabolical plot.

  2. pertaining to or actuated by a devil.


diabolical British  
/ ˌdaɪəˈbɒlɪkəl /

adjective

  1. excruciatingly bad; outrageous

  2. (intensifier)

    a diabolical liberty

"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


Etymology

Origin of diabolical

First recorded in 1500–10; from Late Latin diabolicus ( see diabolic ( def. )) + -al 1 ( def. )


Explanation

Diabolical means "evil." This is a strong word. Too much math homework might seem unfair, but it probably isn't diabolical. Diabolical is related to the Spanish word diablo, which means "devil." In many religions and mythologies, you can't get any more evil than a devil, so diabolical is a powerful term, stronger than even despicable, which is another strong word for things that are hateful. Diabolical things are also intentional. If you got hit by lightning, that's awful and harmful, but it's not diabolical. If someone deliberately runs you over with a car, that's much more diabolical.

Keep Reading on Vocabulary.com

Vocabulary lists containing diabolical

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:

In the scene, set just before the events of 2002’s “Resident Evil,” executives at the diabolical Umbrella Corporation gather to discuss the world’s impending end.

From Salon ● Sep. 23, 2026

The Los Angeles Times described Mold-A-Ramas as “a diabolical cross between a jukebox and a pinball machine” that cost $3,600 apiece, or about $39,500 today.

From Los Angeles Times ● Aug. 10, 2026

In later works by Christie and others, diabolical deeds increasingly transpired in villages, hotels, trains, planes, boats and locked rooms.

From The Wall Street Journal ● Feb. 20, 2026

She said: "We've seen the worst care homes - diabolical homes - and they're not inspected for two or three years."

From BBC ● Nov. 6, 2025

Always didactic, he went into a learned exposition of the diabolical properties of cinnabar, but Úrsula paid no attention to him, although she took the children off to pray.

From "One Hundred Years of Solitude" by Gabriel Garcia Marquez

Random Word

Spin the wheel and learn a new word!

Get a word


Vocabulary.com logo
by dictionary.com

Dictionary.com's Learning Companion

Go beyond just looking up words.
Remember them forever with VocabTrainer.

Start training