commencement vs evaporation

commencement

noun
  • The first existence of anything; act or fact of commencing; the beginning. 

  • The day when degrees are conferred by colleges and universities upon students and others. 

  • A graduation ceremony, from a school, college or university. 

evaporation

noun
  • The process in which all or a portion of liquid (in a container) is turned into vapour, in order to increase the concentration of solid matter in the mixture. 

  • The process of a liquid converting to the gaseous state. 

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