calm vs refractory

calm

verb
  • To become calm. 

  • To make calm. 

noun
  • The state of being calm; peacefulness; absence of worry, anger, fear or other strong negative emotion. 

  • A period of time without wind. 

  • The state of being calm; absence of noise and disturbance. 

adj
  • with few or no waves on the surface; not rippled. 

  • Peaceful, quiet, especially free from anger and anxiety. 

  • Free of noise and disturbance. 

  • Without wind or storm. 

refractory

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

adj
  • Obstinate and unruly; strongly opposed to something. 

  • Not affected by great heat. 

  • Difficult to treat. 

  • Incapable of registering a reaction or stimulus. 

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