levirate (n.)youdaoicibaDictYouDict[levirate 词源字典]
custom by which the male next-of-kin of a dead man was bound to marry his widow, 1725, from Latin levir "brother-in-law" (from PIE *daiwer- "husband's brother") + -ate (2).[levirate etymology, levirate origin, 英语词源]