mischief的意思是淘气;恶作剧;顽皮;恶意;使坏的念头;伤害;毁损。
牛津词典：
noun
[U]
1、淘气；恶作剧；顽皮。
bad behaviour (especially of children) that is annoying but does not cause any serious damage or harm.
Those children are always getting into mischief .
那些孩子总是淘气。
I try to keep out of mischief .
我尽量不胡闹。
It's very quiet upstairs; they must be up to some mischief !
楼上很安静。他们一定在搞什么恶作剧。
2、恶意；使坏的念头。
the wish or tendency to behave or play in a way that causes trouble.
Her eyes were full of mischief.
她眼睛里满是使坏的神情。
3、(formal)?伤害；毁损。
harm or injury that is done to sb or to their reputation.
The incident caused a great deal of political mischief.
这一事件造成了严重的政治危害。