incentive vs vendetta

incentive

noun
  • Something that motivates, rouses, or encourages. 

  • A bonus or reward, often monetary, to work harder. 

adj
  • Inciting; encouraging or moving; rousing to action; stimulating. 

  • Serving to kindle or set on fire. 

vendetta

noun
  • A motivational grudge against a person or faction, which may or may not be reciprocated; the state of having it in for someone. 

  • Revenge. 

  • A bitter, destructive feud, normally between two families, clans, or factions, in which each injury or slaying is revenged: a blood feud. 

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