隠かくし通とおす

godan verb (-su), transitive verb

keep secret; conceal completely; hide until the end

Emphasizes successfully hiding something all the way through, without ever revealing it. Often used for secrets, true feelings, or facts one intends to take to the grave.

• 彼かれは最さい後ごまで真しん実じつを隠かくし通とおした。

  He kept the truth hidden to the very end.

• あの事じ件けんのことは一いっ生しょう隠かくし通とおすつもりだ。

  I intend to keep that incident a secret for the rest of my life.