internecine vs productive

internecine

adj
  • Mutually destructive; most often applied to warfare. 

  • Characterized by struggle within a group, usually applied to an ethnic or familial relationship. 

productive

adj
  • Of a cough, producing mucus or sputum from the respiratory tract. 

  • Of inflammation, producing new tissue. 

  • Capable of producing something, especially in abundance; fertile. 

  • Of, or relating to the creation of goods or services. 

  • Consistently applicable to any of an open set of words. 

  • Yielding good or useful results; constructive. 

  • A type of set of natural numbers, related to mathematical logic. 

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