From The Art and Popular Culture Encyclopedia
Dione in Greek mythology is a vague goddess presence who has her most concrete form in Book V of Homer's Iliad as the mother of Aphrodite. Aphrodite journeys to Dione's side after she has been wounded in battle while protecting her favorite son Aeneas. In this episode, Dione seems to be the equivalent of Gaia the Earth Mother, whom Homer also placed in Olympus, and to that extent might be classed as a "mother goddess". Dione's Indo-European name is really less a name than simply a title: the "Goddess", etymologically a female form of Zeus. After the Iliad, Aphrodite herself was sometimes referred to as "Dionaea" and even "Dione", just "the goddess" (Peck 1898).
Roman "Diana" has a similar etymology but is not otherwise connected with Dione.