deviation vs variance

deviation

noun
  • For interval variables and ratio variables, a measure of difference between the observed value and the mean. 

  • A detour to one side of the originally-planned flightpath (for instance, to avoid weather); the act of making such a detour. 

  • A detour in a road or railway. 

  • The act of deviating; wandering off the correct or true path or road. 

  • The voluntary and unnecessary departure of a ship from, or delay in, the regular and usual course of the specific voyage insured, thus releasing the underwriters from their responsibility. 

  • The shortest distance between the center of the target and the point where a projectile hits or bursts. 

  • A departure from the correct way of acting. 

  • The signed difference between a value and its reference value. 

  • The state or result of having deviated; a transgression; an act of sin; an error; an offense. 

variance

noun
  • A difference between what is expected and what is observed; deviation. 

  • A discrepancy between two legal documents. 

  • A departure from a cause of action originally in a complaint. 

  • An official permit to do something that is ordinarily forbidden by regulations. 

  • The act of varying or the state of being variable. 

  • The state of differing or being in conflict. 

  • The number of degrees of freedom in a system. 

  • Covariance and contravariance generally. 

  • The second central moment in probability. 

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