concurrency vs togetherness

concurrency

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

  • 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. 

togetherness

noun
  • The result or product of being together. 

  • The state or quality of being together. 

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