frankpledge vs matricide

frankpledge

noun
  • A form of collective suretyship and punishment under English law among the members of a tithing. 

  • A decener: a member of a tithing bound in frankpledge. 

  • Any group so similarly answerable for the conduct of all its members and liable for collective punishment. 

  • The tithing itself. 

matricide

noun
  • The killing of one's mother. 

  • A person who kills his or her mother. 

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