fiendish
Americanadjective
adjective
-
of or like a fiend
-
diabolically wicked or cruel
-
informal extremely difficult or unpleasant
a fiendish problem
Other Word Forms
- fiendishly adverb
- fiendishness noun
Etymology
Origin of fiendish
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.
To make up for it, he pulled out a completely different jumping pass on the fly, starting with a different quad—-and then landed another fiendish combination.
From The Wall Street Journal • Feb. 9, 2026
That is good news for Inter who have a fiendish run of fixtures to close their league phase campaign, including clashes at the San Siro with Liverpool and Premier League leaders Arsenal.
From Barron's • Nov. 5, 2025
Atencio’s fiendish feline would have followed guests throughout the ride, a creature said to despise living humans and with predatory, possessive instincts.
From Los Angeles Times • Nov. 5, 2025
The only advice Ms Keast-Butler gave BBC Breakfast earlier on Wednesday was to work in a team and "bring a rich mix of minds" to the fiendish puzzle.
From BBC • Dec. 11, 2024
Clyde’s fiendish mind has not stopped at so simple an abasement, however.
From "A Confederacy of Dunces" by John Kennedy Toole
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.
