abend vs expunge

abend

verb
  • To terminate abnormally. 

noun
  • The abnormal termination of a program. 

  • Termination of a process prior to completion. 

expunge

verb
  • To eliminate completely; to annihilate. 

  • To delete permanently (e-mail etc.) that was previously marked for deletion but still stored. 

  • To erase or strike out. 

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