Synonyms:
demonic, diabolic, diabolical, fiendish, hellish, infernal, satanic, unholy
Meaning: 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"
Synonyms:
devilish, diabolic, diabolical, mephistophelian, mephistophelean
Meaning: showing the cunning or ingenuity or wickedness typical of a devil; "devilish schemes"; "the cold calculation and diabolic art of some statesmen"; "the diabolical expression on his face"; "a mephistophelian glint in his eye"
Usage examples
And the diabolical ingenuity with which he managed, at the close of every over, to change his end!
There must have been some damnable taint in the blood of the common ancestor--a spice of the insane and the diabolical.
As the cooling process went on she began to wonder whether it was worsted alone that had prompted her friend's diabolical suggestion.
Perhaps if such a prohibition had never been made Capitola would never have thought of doing the one or the other; but we all know the diabolical fascination there is in forbidden pleasures for young human nature.