This thesis intends to contribute to a global understanding of the Greek riddle through an analysis of its lexical and semantic field, of the theories devised in ancient times, and of the main sources. The ancient data is put into perspective by means of a status quaestionis in the disciplines of anthropology and folklore studies. The first part of the study is dedicated to the etymological, semantic, syntactic, and statistical examination of the words "ainigma" and "griphos", together with their cognate forms and Latin calques, by way of a corpus analysis utilizing the most recent databases. In the second part, the observation of the conceptions of the riddle attested in the Greek and Latin scholarly texts, from the classical period to the Byzantine commentaries, reveals the extent to which the theorizing of this traditional genre was hindered. The third part of this work deals with the main testimonies of the Greek tradition: the section on riddles in Athenaeus' "Deipnosophists" (Book X, 448 b-459 c), of which we provide a critical edition and a French translation, and the items preserved in the "Greek Anthology" (Book XIV), here translated as well; the riddles collected in both sources are then analysed according to a typological framework. The riddle thus appears as a literary genre, as a discursive genre, and as a category of reception. Already in ancient times enigmatic speech involves a reflexive look at the forms of language, communication and culture.
