abend vs sever

abend

verb
  • To terminate abnormally. 

noun
  • The abnormal termination of a program. 

  • Termination of a process prior to completion. 

sever

verb
  • To disconnect; to disunite; to terminate. 

  • To make a separation or distinction; to distinguish. 

  • To cut free. 

  • To suffer disjunction; to be parted or separated. 

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