fratricide
/ˈfrætrɪsaɪd/noun
mass noun
1- the killing of one's brother or sister杀兄弟（或姐妹）。
1.1
- count noun a person who kills their brother or sister杀兄弟（或姐妹）的人。
1.2
- mass noun the accidental killing of one's own forces in war（战争中的）误杀本方人员。
词源
late 15th cent. （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）.