diabolical

adjective

di·​a·​bol·​i·​cal ˌdī-ə-ˈbä-li-kəl How to pronounce diabolical (audio)
variants or diabolic
: of, relating to, or characteristic of the devil : devilish
a diabolical plot
diabolically adverb
diabolicalness noun

Did you know?

Like the word devil, "diabolical" traces back to Latin diabolus, which itself descends from Greek diabolos, a word that literally means "slanderer." In English, "diabolical" has many nuances of meaning. It can describe the devil himself (as in "my diabolical visitor") or anything related to or characteristic of him in appearance, behavior, or thought; examples include "diabolical lore," "a diabolical grin," and "a diabolical plot." In British slang, "diabolical" can also mean "disgraceful" or "bad," as in "the food was diabolical."

Examples of diabolical in a Sentence

the police quickly mobilized to track down the diabolical criminals before they struck again
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Not even Chris Hargensen, the organizer of Carrie’s prom-night humiliation, the meanest of all mean girls, could have thought up something so diabolical. Rafaela Bassili, Vulture, 10 Sep. 2025 Yet, as time passes, the pair end up engaging in a full-blown and increasingly diabolical war. Aramide Tinubu, Variety, 10 Sep. 2025 Their challenge on Frankenstein was bringing to the big screen the horror-meister’s vision of egotistical scientist Victor Frankenstein and his monster as part of a diabolical experiment. Etan Vlessing, HollywoodReporter, 6 Sep. 2025 Some don’t think about it; others call it exhilarating or existential, even diabolical. Sumera Riaz, Forbes.com, 27 Aug. 2025 See All Example Sentences for diabolical

Word History

Etymology

diabolical from diabolic + -ical; diabolic going back to Middle English deabolik, borrowed from Middle French & Late Latin; Middle French dyabolique, borrowed from Late Latin diabolicus, borrowed from Late Greek diabolikós, going back to Greek, "slanderous," from diábolos "accuser, backbiter, slanderer" + -ikos -ic entry 1 — more at devil entry 1

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of diabolical was in the 15th century

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Cite this Entry

“Diabolical.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diabolical. Accessed 11 Sep. 2025.

Kids Definition

diabolical

adjective
di·​a·​bol·​i·​cal ˌdī-ə-ˈbäl-i-kəl How to pronounce diabolical (audio)
variants or diabolic
: of, relating to, or characteristic of the devil : fiendish
diabolically adverb
diabolicalness noun
Last Updated: - Updated example sentences
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