fratricide
noun
[ ˈfratrɪsʌɪd ]
• the killing of one's brother or sister.
• "Cain justifies his fratricide with lethal logic"
Origin:
late 15th century (denoting a person who kills their brother or sister, derived from Latin fratricida ): the primary current sense comes via French from late Latin fratricidium, from frater ‘brother’ + -cidium (see -cide).
