dismission vs expulsion

dismission

noun
  • The act of dismissing or sending away (someone). 

  • Removal from office; termination of employment or services, or position in ones affections. 

  • The setting aside (of something) from consideration. 

expulsion

noun
  • The act of expelling or the state of being expelled. 

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