deep six

/D IY1 P S IH0 K S/
verb
  1. 1

    (informal, idiomatic, transitive) To discard, get rid of, or cancel; to completely put an end to something.

  2. 2

    (informal, idiomatic, transitive, uncommon) To submerge (something) in water.

noun
  1. 1

    (informal, idiomatic) An ejection, discardment or destruction.

  2. 2

    (informal, idiomatic) The grave or death; also, the (notional) place where something is discarded.