sororicide vs uxoricide

sororicide

noun
  • A person who kills his or her sister. 

  • The killing of one's sister. 

uxoricide

noun
  • One who murders his or her wife. 

  • The murdering of one's own wife. 

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