House Arrest
noun, する verb
Soft prohibition isn't going to be as bad as jail or prison. They went soft on you, so you're only under house arrest. That's not so bad, right?
なんきん
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
彼女は自宅軟禁下に置かれました。
She was placed under house arrest.