haunt vs incubator

haunt

noun
  • A lair or feeding place of animals. 

  • A place at which one is regularly found; a habitation or hangout. 

  • A ghost. 

verb
  • To stalk; to follow. 

  • To accustom; habituate; make accustomed to. 

  • To inhabit or to visit frequently (most often used in reference to ghosts). 

  • To make uneasy, restless. 

  • To practise; to devote oneself to. 

  • To persist in staying or visiting. 

incubator

noun
  • A place to maintain the culturing of bacteria at a steady temperature. 

  • An apparatus used to maintain environmental conditions suitable for a newborn baby. 

  • Any apparatus used to maintain environmental conditions suitable for a reaction. 

  • A support programme for the development of entrepreneurial companies. 

  • An apparatus used to maintain environmental conditions suitable for the hatching of eggs. 

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