Definition of "sororicide"

sororicide¹

noun
countable and uncountable, plural sororicides
1. The killing of one's sister.
  Quotations
  Terms related to familicide include filicide (the killing of one's child or children), uxoricide (the killing of one's wife), fratricide or sororicide (the killing of one's brother or sister), avunculicide (the killing of one's uncle), and nepoticide (the killing of one's nephew).
  2014, Albert Lee Strickland, “Familicide”, in Michael John Brennan, editor, The A–Z of Death and Dying: Social, Medical, and Cultural Aspects, Santa Barbara, Calif.: Greenwood Publishing Group, pages 205–206

sororicide²

noun
plural sororicides
1. A person who kills his or her sister.