- hellish; fiendish; diabolical: an infernal plot.
- extremely troublesome, annoying, etc.; outrageous: an infernal nuisance.
- of, inhabiting, or befitting hell.
- Classical Mythology. of or relating to the underworld.
Origin of infernal
SynonymsSee more synonyms on Thesaurus.com
Examples from the Web for infernal
Infernal, it can cause fires and explosions; toxic, it can debilitate, poison, and kill.The Fiery Underground Oil Pit Eating L.A.
December 6, 2014
He called her “a silly chattering windbag, an infernal liar, a conceited, gushing, rump-wagging, blethering ass.”Gertrude of Arabia, the Woman Who Invented Iraq
June 17, 2014
Egypt is eternal, one might say, but its problems are infernal.Egypt’s Arab Spring Gives Way To Spring Of The Patriarch
January 10, 2014
That infernal device was much like the ones made from pressure cookers used in Boston.The Story Behind the Bombers
Christopher Dickey, Eli Lake, Daniel Klaidman
April 19, 2013
Of course there will be deranged people who will rejoice in their weird conviction of his eternal and infernal roasting.Christopher Hitchens Is Hailed by Stephen Fry as a Man of Style and Wit
December 17, 2011
The lake by which the ancients entered the infernal regions.The Devil's Dictionary
And then—I might at a pinch describe the infernal regions, but not the other place.American Notes
He is treated from that instant as a man who has done some infernal action.Little Dorrit
It seemed to me that he was Pluto, the god of the infernal regions, and I was Proserpine.My Double Life
How long I stood for this infernal proceeding I do not know.City of Endless Night
- of or relating to an underworld of the dead
- deserving hell or befitting its occupants; diabolic; fiendish
- informal irritating; confounded
Word Origin and History for infernal
late 14c., in reference to the underworld, from Old French enfernal, infernal (12c.), from Late Latin infernalis "of the lower regions," from infernus "hell" (Ambrose), literally "the lower (world)," noun use of Latin infernus "lower, lying beneath," from infra "below" (see infra-). Meaning "devilish, hateful" is from early 15c. For the name of the place, or things which resemble it, the Italian form inferno has been used in English since 1834, from Dante. Related: Infernally.