immortal vs undiminishable

immortal

adj
  • Not susceptible to death; living forever; never dying. 

  • Connected with or relating to immortality. 

  • Never to be forgotten; that merits being always remembered. 

noun
  • One who is not susceptible to death. 

  • A member of an elite regiment of the Persian army. 

  • A member of the Académie française. 

  • An administrator of a multi-user dungeon. 

undiminishable

adj
  • Unable to be diminished. 

How often have the words immortal and undiminishable occurred in a corpus of books? (source: Google Ngram Viewer )