Nomadic herders of southern Kenya and northern Tanzania. They speak a language (usually called Maa) of the Nilo-Saharan family. Numbering some 900,000, the Masai subsist almost entirely on the meat, blood, and milk of their cattle herds. A kraal, consisting of a large circular thornbush fence around a ring of mud-dung houses, holds four to eight families and their herds. Polygamy is common among older men. All men are grouped into age sets. Young men traditionally live in isolation in the bush for varying lengths of time in order to develop strength, courage, and endurance. See alsoNilot.