Define Sororate.

"Sororate" is a cultural and anthropological term that refers to a marital custom or practice in which a man, upon the death of his wife or her inability to fulfill her marital duties, marries one or more sisters of his deceased or incapacitated wife. The sororate system is a form of marriage that involves the replacement of a wife with her sister(s) within the same marriage arrangement.

In societies where sororate is practiced, the primary goal is often to maintain continuity in the family unit, ensure the well-being of the widower, and preserve social and economic ties. The practice is rooted in cultural norms, kinship structures, and the idea of maintaining familial alliances through marriage.

Sororate contrasts with a similar practice called "levirate," where a man is obligated to marry the widow of his deceased brother. Both sororate and levirate have been observed in various cultures globally, and their prevalence is often linked to specific social, religious, or traditional beliefs governing family structures and relationships.