concurrency vs fitness

concurrency

noun
  • A property of systems where several processes execute at the same time. 

  • A stretch of road that is shared between two or more numbered or named routes. 

  • The property or an instance of being concurrent; something that happens at the same time as something else. 

fitness

noun
  • The condition of being attractive, fanciable or beautiful. 

  • The cultivation of an attractive and/or healthy physique. 

  • The condition of being fit, suitable or appropriate. 

  • An organism's or species' degree of success in finding a mate and producing offspring. 

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