dispersal vs reinforcement

dispersal

noun
  • The act or result of dispersing or scattering; dispersion. 

  • A dispersal prison. 

reinforcement

noun
  • The process whereby a behavior with desirable consequences comes to be repeated. 

  • A small round white sticker placed around a punched hole in a piece of paper to prevent the binder's rings from tearing through the paper. 

  • Additional troops or materiel sent to support a military action. 

  • The act, process, or state of reinforcing or being reinforced. 

  • A thing that reinforces. 

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