[1] : The Collaborative International Dictionary of English v.0.48

hellish \hell"ish\, a.
   of or pertaining to hell; like hell; infernal; malignant;
   wicked; detestable; diabolical. "hellish hate." --milton. --
   hell"ishly, adv. -- hell"ishness, n.
   1913 webster
see also:
hell"ishly hell"ishness 

[2] : WordNet (r) 2.0

hellish
     adj 1: very unpleasant; "hellish weather"; "stop that god-awful
            racket" syn: beastly, god-awful
     2: 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" syn: demonic, diabolic,
         diabolical, fiendish, infernal, satanic, unholy
see also:
beastly god-awful demonic diabolic diabolical fiendish 
infernal satanic unholy 

[3] : Moby Thesaurus II by Grady Ward, 1.0

98 moby thesaurus words for "hellish":
   acherontic, draconian, lethean, mephistophelian, plutonian,
   plutonic, stygian, tartarean, anarchic, angry, animal,
   anthropophagous, atrocious, barbaric, barbarous, beastly, bestial,
   bloodthirsty, bloody, bloody-minded, blustering, blusterous,
   blustery, brutal, brutalized, brute, brutish, cannibalistic,
   chaotic, chthonian, chthonic, cruel, cruel-hearted, cursed,
   damnable, demoniac, demoniacal, demonic, demonish, demonlike,
   devil-like, devilish, diabolic, execrable, fell, feral, ferocious,
   fiendish, fiendlike, fierce, frantic, frenzied, furious, ghoulish,
   hellborn, infernal, infuriate, inhuman, inhumane, insensate, mad,
   mindless, murderous, ogreish, orgasmic, orgastic, pandemoniac,
   pandemonic, purgatorial, raging, ravening, raving, rip-roaring,
   ruthless, sadistic, sanguinary, sanguineous, satanic, savage,
   sharkish, slavering, storming, stormy, subhuman, sulfurous,
   tempestuous, troublous, truculent, tumultuous, turbulent,
   unchristian, uncivilized, ungodly, unhuman, uproarious, vicious,
   wild, wolfish

Hellish >> H Words
Hellish, definition of term: Hellish
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