sororicide: Meaning and Definition of

so•ror•i•cide

Pronunciation: (su-rôr'u-sīd", -ror'-), [key]
— n.
  1. a person who kills his or her sister.
  2. the act of killing one's own sister.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.