fratricidium
From LSJ
ἔνθα οὐκ ἔστι πόνος, οὐ λύπη, οὐ στεναγμός, ἀλλὰ ζωὴ ἀτελεύτητος → where there is no pain, no sorrow, no sighing, but life everlasting
Latin > English (Lewis & Short)
frātrĭcīdĭum: ii, n. fratricida,
I the murder of a brother. fratricide (eccl. Lat.), Tert. Monog. 4; Hier. adv. Jovin. 1, 14; Salv. de Gub. Dei, 1, p. 25.