• WordNet 3.6
    • adj fiendish extremely evil or cruel; expressive of cruelty or befitting hell "something demonic in him--something that could be cruel","fires lit up a diabolic scene","diabolical sorcerers under the influence of devils","a fiendish despot","hellish torture","infernal instruments of war","satanic cruelty","unholy grimaces"
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Webster's Revised Unabridged Dictionary
    • a Fiendish Like a fiend; diabolically wicked or cruel; infernal; malignant; devilish; hellish.
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Century Dictionary and Cyclopedia
    • fiendish Having the qualities of a fiend; characteristic of a fiend; demoniacal; extremely wicked, cruel, or malicious; devilish: as, a fiendish persecutor; fiendish laughter.
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Chambers's Twentieth Century Dictionary
    • adj Fiendish like a fiend; malicious
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Chambers's Twentieth Century Dictionary
A.S. feónd, pr.p. of feón, to hate; Ger. feind, Dut. vijand.


In literature:

But the Captain suddenly developed an inexcusable and fiendish energy.
"The Killer" by Stewart Edward White
As a Show Girl, it has been my lot to be provided with one of these fiendish devices of medieval days.
"Biltmore Oswald" by J. Thorne Smith, Jr.
Ye gods, what a fiendish night!
"The Safety Curtain, and Other Stories" by Ethel M. Dell
You, her father, planned that fiendish act!
"Bad Hugh" by Mary Jane Holmes
The German bayonet is a fiendish weapon.
"Private Peat" by Harold R. Peat
Thirdly, deities appear in various forms, described as mild, angry or fiendish.
"Hinduism and Buddhism, An Historical Sketch, Vol. 3 (of 3)" by Charles Eliot
Outside the window a gun is making a fiendish row, shaking the whole house.
"Adventures of a Despatch Rider" by W. H. L. Watson
She hoped he was not going to get into one of his fiendishly unpleasant moods.
"The Bad Man" by Charles Hanson Towne
The human heart, though fallen, is not fiendish.
"Two Old Faiths" by J. Murray Mitchell and William Muir
Fiendish slaughter of women by Arabs.
"The Last Journals of David Livingstone, in Central Africa, from 1865 to His Death, Volume II (of 2), 1869-1873" by David Livingstone

In poetry:

Snatched the purple billows o'er,
Through the fiendish rage and roar,
To the far and peaceful shore;
--Slain in battle!
"Beechenbrook - X" by Margaret Junkin Preston
'Tis all a tale of fiendish art—
Thou com'st, my love, to prove it so!
I'll press thy hand upon my heart—
It chills me like a hand of snow!
"The Mad Lover" by Washington Allston
Through clouds of fiendish greed and wicked spite,
a sinister shadow crept near,
a gold-armoured monster reared his height
dripping with blood and human tears.
"A Youth" by Hristo Smirnenski
At length one furious demon grasped the sun
And sped away as fast as he could run,
And with a ringing laugh of fiendish mirth,
He leaped the battlements and fell to earth.
"A Servian Legend" by Ella Wheeler Wilcox
And now his fiendish crime has been avenged;
Let us back to our wives and children. — Say,
What did he mean by those last muttered words,
"Brothers in spirit, brothers in deed are we"?
"Brothers" by James Weldon Johnson
"Twenty years in the Yukon, struggling along its creeks;
Roaming its giant valleys, scaling its god-like peaks;
Bathed in its fiery sunsets, fighting its fiendish cold —
Twenty years in the Yukon . . . twenty years — and I'm old.
"The Parson's Son" by Robert W Service

In news:

Outside of serving as a fiendish prop in a great Edgar Allen Poe story, sherry has suffered a horrible rap.
What's the matter with the grimly fiendish stage treatment of Coraline.
Over the past three years, al-Qaida bomb makers in Yemen have developed three fiendishly clever devices in hopes of attacking airplanes in the skies above the United States.
Accused cannibal cop's fiendish plot no fantasy: federal prosecutors.
How 007's fiendish foes changed to reflect the times.
Fiendish footwear require exorcism.
OFWGKTA's " Goblin " Fiendishly Good.
Hunter Foster plays Seymour, in thrall to the fiendish flora Audrey, in 'Little Shop of Horrors,' retooled for its Broadway run at the Virginia Theater.
To his critics, he was devilish all right -- as in fiendishly manipulative.
The particles involved are neutrinos , fiendishly difficult to work with because they rarely interact with matter.
Lou Berney immediately earned a seat of honor at the mystery masters' table with his crackling caper novel, "Gutshot Straight" - a lightning-fast, fiendishly clever suspensor that screamed for a sequel.
Fiendish footwear require exorcism .
As a genre and a style, " goth " is pretty easy to stereotype (see The Damned's "Grimly Fiendish" for a particularly campy version), but the truth is its influence spreads far and wide.
(Determining the rate of money supply growth is fiendishly difficult.
Two adorable books appeared in the mail recently: Chris Marks' Horrorgami: 25 Creepy Creatures, Ghastly Ghouls, and Other Fiendish Paper Projects (Running Press, 128 pp.

In science:

For instance, switching a paginated journal so that it utilizes article numbering sounds easy, but it is fiendishly complicated because it affects bibliographic coordinates and every system that uses them (Chaix 2010).
Fully Digital: Policy and Process Implications for the AAS