Secret society, any of a large range of membership organizations or associations that utilize secret initiations or other rituals and whose members often employ unique oaths, grips (handshakes), or other signs of recognition. Elements of secrecy may vary from a mere password to elaborate rituals, private languages, costumes, and symbols. The term may be applied to such widely divergent groups as U.S. college fraternities and sororities, the Ku Klux Klan, and international Freemasonry as well as to similar phenomena in ancient or precolonial cultures.

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