Cal·lis·to (kə-lĭs

tō)
n.► Greek Mythology. A nymph, beloved of Zeus and hated by Hera. Hera changed her into a bear, and Zeus then placed her in the sky as the constellation Ursa Major.
► One of the four brightest satellites of Jupiter and the eighth in distance from the planet. Originally sighted by Galileo, it is the largest planetary satellite.
[TahlilGaran] American Dictionary ▲