cooperative vs refractory

cooperative

noun
  • A type of company that is owned partially or wholly by its employees, customers or tenants. 

adj
  • Ready to work with another person or in a team; ready to cooperate. 

  • Involving cooperation between individuals or parties. 

  • Relating to a cooperative or cooperatives. 

refractory

adj
  • Obstinate and unruly; strongly opposed to something. 

  • Not affected by great heat. 

  • Difficult to treat. 

  • Incapable of registering a reaction or stimulus. 

noun
  • A material or piece of material, such as a brick, that has a very high melting point. 

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