noun
backbiting; criticizing behind one's back
Almost always used in the passive phrase 後ろ指を指される, meaning 'to be talked about behind one's back' or 'to be the target of backbiting'.
See also: 後ろ指を指される
彼は陰で後ろ指を指されるようなことは何もしていない。
He hasn't done anything that would make people talk behind his back.
あの政治家はいつも後ろ指を指されている。
That politician is always being criticized behind his back.