It is proposed that middle- and upper-middle-class slang used among white young people in modern America shows age-related themes. For youngsters between the ages of eight and early adolescence, the major theme in slang use is to establish in-group and out-group membership, with standards of judgment based on clothes, manners, and physical appeal. From middle adolescence through the college years, the central theme is concerned with censuring bad judgment on the part of the individual. Slang usage during this time stigmatizes impulsive behavior and injudicious values in sex, drugs, and personal interests. In the period between a person's middle and late twenties, the major slang theme is in reinforcing responsible performance in one's career or on the job, through an emphasis in which thoughtfulness and dedication are praised. In general, slang is viewed as historicist, determinist, and materialist: when combined with a narrowly selective word-analytic cognitive style in the middle class, slang forms attitudes and emotional "gestalten" that transcend age-graded use and may influence an individual's pattern of thinking for his entire life. The theoretical background for this view is outlined, and evidence is presented. (MSE)