Abstract : This dissertation aims at providing a panorama of the magicoverbal belief, i.e. the belief that words are endowed with an intrinsic supernatural power: wishes, imagined things or events could come true just because they have been uttered or simply thought of. Although this dissertation is descriptive, it is explanatory also, inasmuch as the representations of a magical power of words are investigated not only to document its manifestations, but also to understand why they could be responsible of certain behaviors or reactions, and with what implications. Who are these persons who seem to believe in word magic? Are they as naive as is usually assumed or is it but a persistent prejudice? Is such a representation of language homogeneous or does it show variations? What is it conditioned by? What are its mechanisms and modalities of emergence? The dissertation is divided into three parts: the first one deals with the field of investigation, the methodology (chapter 1), and the results (chapter 2). The analysis and interpretation of the results (chapter 3) make the second part. As to the third one, it deals with the mechanisms of the magicoverbal belief (chapter 4).