The aim of the paper is to analyse the role of wordformation motivation in child’s language development. The character of the research problem requires a transdisciplinary approach. For this reason, the author looks back on derivational theories as well as on researches of applied linguistics in Slovakia and abroad. Analysis of the relation between wordformation motivation and language development is based on author’s empirical findings on the children’s nonce words, the role of wordformation motivation in the development of the child’s cognitive and linguistic abilities and in the comprehension of an instructional text. The paper consists of: 1) the analysis of theoretical background from the point of view of derivatology as well as of applied linguistics; 2) the analysis of relevant research findings and the clarification of relationship between particular aspects of this topic; 3) the discussion about the functions of wordformation motivation in child’s language development confronting the author’s findings with the findings of other researches in this field.