operant vs productive

operant

adj
  • That operates to produce an effect. 

noun
  • Any of a class of behaviors that produce consequences by operating (i.e., acting) upon the environment. 

  • An operative person or thing. 

productive

adj
  • Yielding good or useful results; constructive. 

  • 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. 

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

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