Definition of fiendish adjective from the Oxford Advanced Learner's Dictionary



    BrE BrE//ˈfiːndɪʃ//
    ; NAmE NAmE//ˈfiːndɪʃ//
    [usually before noun]
    jump to other results
  1. 1cruel and unpleasant a fiendish act shrieks of fiendish laughter
  2. 2(informal) extremely clever and complicated, often in an unpleasant way a puzzle of fiendish complexity a fiendish plan
  3. 3(informal) extremely difficult a fiendish problem
See the Oxford Advanced American Dictionary entry: fiendish