impassive vs lifeless

impassive

adj
  • Still or motionless. 

  • Having, or revealing, no emotion. 

lifeless

adj
  • dead; having lost life 

  • inanimate; having no life 

  • dull or lacking vitality 

  • uninhabited, or incapable of supporting life 

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