诽谤;诋毁
to criticize or make damaging remarks or judgments about someone or something
His opponents cast aspersions on his patriotism. 反对者诋毁他的爱国精神。
Several former friends and allies have come forward to cast aspersions on his character.
It's interesting that she chose this moment to cast aspersions on his ability as a coach.
You shouldn't cast aspersions on him before you've gotten to know him.
I wouldn't like to cast aspersions on the quality of his work.
See also: cast verb (DOUBT)