Synonyms for diabolic

Adjective

1. devilish, diabolic, diabolical, mephistophelian, mephistophelean, evil (vs. good), wicked

usage: 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"

2. demonic, diabolic, diabolical, fiendish, hellish, infernal, satanic, unholy, evil (vs. good), wicked

usage: 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"