complainant vs interpleader

complainant

noun
  • The party that brings a civil lawsuit against another; the plaintiff. 

  • One who makes complaint. 

  • An alleged victim in a criminal investigation or trial. 

interpleader

noun
  • Motion for a third party to enter into a lawsuit in process because a matter is being adjudicated in which they have an interest. 

  • Process by which a third party asks a court to determine which of two rival claims is to be honored by the third party. 

  • One who makes an interplea. 

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