Classical Mythology. any of the sons of Uranus and Gaea, including Coeus, Crius, Cronus, Hyperion, Iapetus, and Oceanus. Also, Titaness. any of the sisters of these, including Mnemosyne, Phoebe, Rhea, Tethys, Themis, and Thia. any of the offspring of the children of Uranus and Gaea.