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diabolical

1 ENTRIES FOUND:
diabolical /ˌdajəˈbɑːlɪkəl/ adjective
diabolical
/ˌdajəˈbɑːlɪkəl/
adjective
Britannica Dictionary definition of DIABOLICAL
[more diabolical; most diabolical]
also diabolic /ˌdajəˈbɑːlɪk/ : extremely evil
Diabolical often describes a plot, scheme, etc., that is very clever and that is intended for an evil purpose.
British, informal : very unpleasant, bad, or annoying

— diabolically

/ˌdajəˈbɑːlɪkli/ adverb