u/commiespaceinvader discusses that in the first portion of his answer here and I address it in the beginning of my answer here

However, neither of us actually notes a portion of the other terms used. Raul Hilberg simply called it The Destruction of the European Jews in his book by that name. Other terms are "the catastrophe" or "the disaster," Khurban (Hebrew for "destruction") or Shoah (Hebrew for catastrophe).