/kɑ:st; US kæst ||; kæst/noun [C,U] a social class or group based on your position in society, how much money you have, family origin, etc; the system of dividing people in this way （根据社会地位、金钱、家庭出身等来划分的）社会等级；种姓制度: Hindu society is based on a caste system. 印度社会是建立在种姓制度上的。