A sorority is a women's social club at an American university. Members usually live together in a large house, choose new members through a selection process each year (called rush), use Greek letters as their name — Kappa Delta, Alpha Phi — and run parties, charity events and lifelong networks of contacts. The male equivalent is a fraternity. This is a strongly American thing; British and Taiwanese universities do not have them, which is why English textbooks outside America rarely explain the word, and why so many films assume you already understand it. The picture in American culture is mixed: for some people a sorority means real friendship and a network that helps you get a job twenty years later, and for others it means money, exclusion, and drinking. Films play on both. There is also a second, much rarer use — sorority meaning sisterhood in a serious sense, women standing together — but you will meet that mainly in writing about feminism, not in ordinary speech.