di·a·bol·i·cal (dī′ə-bŏlĭ-kəl) also di·a·bol·ic (-ĭk)
1. Of, concerning, or characteristic of the devil; satanic.
2. Appropriate to a devil, especially in degree of wickedness or cruelty.
[From Middle English deabolik, from Old French diabolique, from Late Latin diabolicus, from Latin diabolus, devil; see DEVIL.]
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