Palimpsest, pä'limp-sest, n [Gr. palimp-
  sëstos, rubbed again - palin, again, and
  psaö, to rub.] A parchment or other piece
  of writing material from which one wri-
  ting has been erased to make room for
  another, often leaving the first faintly
  visible, a process to which many ancient
  manuscripts were subjected.