centralization vs coupling

centralization

noun
  • The act or process of centralizing, or the state of being centralized; the act or process of combining or reducing several parts into a whole 

coupling

noun
  • The property of physical systems that they are interacting with each other 

  • Sexual intercourse. 

  • Act of joining together to form a couple. 

  • A device that couples two things together. 

  • The degree of reliance between two or more software modules. 

  • A connection between two electronic circuits such that a signal can pass between them. 

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