Music and Time Annotation << Back Small «Jubilee» with Great Drive Lutsker P. Susidko I. The article is dedicated to the question of nomenclature in the Italian opera of XVIIth and XVIIIth centuries. In the focus of attention is the problem of correlation between authentic genre identifications and terms and definitions used later in practice of historians of XIXth and XXth centuries. Three possible ways are proposed for resolving this problem. The first one – to name the genre as we understand today a substance of its poetic and without scrupulous care of historical sources. The second – to hold the principle and consistent authenticity, i.e. to name the genre of any opera composition exclusively as it was fixed in the original score or libretto. However both ways are fraught with unavoidable mistakes that are exemplified in article. The only acceptable is the historical stylistic approach, when terms authenticity combines with systems analysis of genre processes in development of Italian opera in XVIIth and XVIIIth centuries that allow achieving the maximum of historical correctness. Keywords: italian opera of XVIIth and XVIIIth centuries, genre definitions, opera seria, opera buffa, dramma per musica, dramma giocoso, terms authenticity, historical stylistic approach. Contacts: E-mail: lspriv@mail.ru Pp. 07-10.