To determine if children could discriminate among the 24 ways in which words possess meaning (logico-semantic relationships) defined by Evanechko and to see if this ability changed over time, 570 fifth, eighth, and eleventh graders were presented the task of sorting decks of cards containing examples of the 24 categories. Although it was not possible to have subjects sort examples of all 24 relationships at one time, an attempt was made to have groups of subjects work with relationships that were likely to be confused with each other. The results support the validity of the distinction among the 24 logico-semantic relationships. The most important finding was the strong developmental trend that was found both in the increased congruence of the latent categories to the theoretical categorization and in the increased sophistication of the grouping strategies employed by the subjects over age levels. The findings also suggested that greater changes occurred between the fifth and eighth grades than between the eighth and eleventh grades. Future research should explore the development of flexibility in children's word definition abilities. (FL)