in the teeth of sth这个词的意思是“（尽管遇到困难、反对等）不管不顾、直面抵抗”。

【例句】
If something happens or is done in the teeth of difficulties, the difficulties cause problems but do not stop it.
面对困难，直面而上。

The road was builtin the teeth of fierce opposition from the public.
这条道路是在公众的强烈反对下修起来的。