(Πολύμνια), or POLYHY'MNIA, a daughter of Zeus, and one of the nine Muses. She presided over lyric poetry, and was believed to have invented the lyre. (Hes. Th. 78; Schol. ad Apollon. Rhod. 3.1.) By Oeagrus she became the mother of Orpheus. (Schol. l.c. 1.23.) In works of art she was usually represented in a pensive attitude. (Hirt, Mythol. Bilderb. p. 209; comp. MUSAE.)
[L.S]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890