Iacchus
(
Ἴακχος). The solemn name of Bacchus in the Lesser
Eleusinian Mysteries, whose name was derived from the boisterous song called Iacchus. In these
mysteries Iacchus was regarded as the son of Zeus and Demeter, and was distinguished from the
Theban Bacchus (Dionysus), the son of Zeus and Semelé. In some traditions Iacchus
is even called a son of Bacchus, but in others the two are identified. See the chapter on
“Dionysus at Athens” in Dyer's
Gods in Greece (Lond.
and N. Y. 1891); and the articles
Dionysus;
Eleusinia.