calm vs turbulence

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. 

verb
  • To become calm. 

  • To make calm. 

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. 

turbulence

noun
  • The state or fact of being turbulent or agitated; tempestuousness, disturbance. 

  • Disturbance in a gas or fluid, characterized by evidence of internal motion or unrest. 

  • Specifically, a state of agitation or disturbance in the air which is disruptive to an aircraft. 

  • An instance or type of such state or disturbance. 

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