meaning of diabolical2
1. Pertaining to the devil; resembling, or appropriate, or appropriate to, the devil; devilish; infernal; impious; atrocious; nefarious; outrageously wicked; as, a diabolic or diabolical temper or act.
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"