Incipit

(From Lat. incipit = "it begins") Preamble of late antique and medieval manuscripts, which signals the beginning of a new book or an entire work. Since the current use of titles only developed over time, many works were often named after their incipit, which consists of their first words (cf. for example the term "The Moon has Risen" used for the lullaby instead of the actual title "Evening Song").