Diabolical

прилагательное 1) дьявольский Синоним(ы): devilish, damnable 2) злой, жестокий

Большой англо-русский словарь

Diabolical

or diabolic adjective Etymology: Middle English deabolik, from Middle French diabolique, from Late Latin diabolicus, from diabolus of, relating to, or characteristic of the devil; devilish Example: a diabolical plotdiabolically adverbdiabolicalness noun

Merriam-Webster's Collegiate Dictionary