IDIOMS

die out

(idiomatic) To cease gradually.

Example: 1963, Margery Allingham, chapter 1, The China Governess[1]:
  The original family who had begun to build a palace to rival Nonesuch had died out before they had put up little more than the gateway, […].
  The dinosaurs died out a long time ago.‎
  The prejudice has died out.