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English definition of “diabolical”


adjective     /ˌdaɪəˈbɒl.ɪ.kəl/ US  /-ˈbɑː.lɪ.kəl/ (US also diabolic)
informal extremely bad or shocking: Conditions in the prison were diabolical. His driving is diabolical!Serious and unpleasantNot attractive to look atInformal words for bad evil, or caused by the DevilMorally wrong and evilDishonest diabolically     /-ˈbɒl.ɪ.kəl.i/ US  /-ˈbɑː.lɪ.kəl.i/ adverb diabolically (= extremely) clever/wickedMorally wrong and evilDishonest
(Definition of diabolical adjective from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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