lifeless vs spark out

lifeless

adj
  • dead; having lost life 

  • inanimate; having no life 

  • dull or lacking vitality 

  • uninhabited, or incapable of supporting life 

spark out

adj
  • Completely asleep or unconscious. 

verb
  • To render unconscious; to knock out. 

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