Adjective diabolical has 2 senses
- devilish, diabolic, diabolical, mephistophelian, mephistophelean - 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"
Antonym: good (indirect, via evil)
- demonic, diabolic, diabolical, fiendish, hellish, infernal, satanic, unholy - 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"
Antonym: good (indirect, via evil)
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