diabolical

1. ADJ If you describe something as diabolical, you are emphasizing that it is very bad, extreme, or unpleasant. 非常糟糕的; 極度的; 可惡的[非正式]

It was a diabolical error, a schoolboy error. 那是個糟糕透頂的錯誤，一個小學生才會犯的錯誤。

2. diabolicallyADV

...diabolically difficult clues. ...極其難解的線索。