任まかせきり

noun

leaving everything up to someone else; entrusting completely

Describes a situation where one person delegates all responsibility to another and does not get involved afterward. Often used with verbs like する or になる.

• 彼かれに任まかせきりにして、私わたしは何なにも手伝てつだわなかった。

  I left everything up to him and didn't help at all.

• このプロジェクトは彼かの女じょに任まかせきりだ。

  This project has been completely entrusted to her.