Sentence:  The <WSD>sororate</WSD> is frequently associated with the custom of bride price; if the husband′s kindred have “bought” a wife for him and she dies, her family or kindred are obligated to replace her. The institutions of levirate and <WSD>sororate</WSD> are very widespread in primitive society, and in many instances a tribe will observe both customs. 
Meaning of the word marked with <WSD> tags:  The custom of the marriage of a man to the sister of his wife, usually after the wife has died.