dispersal vs dissipation

dispersal

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

  • A dispersal prison. 

dissipation

noun
  • The act of dissipating or dispersing; a state of dispersion or separation; dispersion; waste. 

  • A trifle which wastes time or distracts attention. 

  • A loss of energy, usually as heat, from a dynamic system. 

  • A dissolute course of life, in which health, money, etc., are squandered in pursuit of pleasure; profuseness in immoral indulgence, as late hours, riotous living, etc.; dissoluteness. 

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