The study is a preliminary investigation on the role of iconic and linguistic codes in the definition of basic level nouns. Relations between performance achieved by preschool (5-years-old) and school (6/7-years-old) children in a visuo-spatial (chess-boards), a phono-articulatory (non-word recognition), a categorisation task and a definition task were analysed. Moreover, 6/7-years-old children have been divided into "high and low visualizers", "high and low verbalizers" and "high and low categorizers" and their definitions have been compared. In agreement with the literature on imagery, results showed a preference for the use of iconic strategies of representation in younger children. Instead, school children's performance in imaginative and verbal tasks were useful to differentiate the groups on the basis of the quality of their definitions: high verbalizers and low visualizers produced more formally good definitions (presence of the superordinate).