Hades three-headed guard dog Cerberus. The Etruscan god Aita and the Roman gods Dis Pater and Orcus were eventually taken as equivalent to Hades and merged into Pluto, a Latinization of Plouton (", Ploútōn"), itself a euphemistic title often given to Hades. The origin of Hades' name is uncertain, but has generally been seen as meaning "the unseen one" since antiquity. An extensive section of Plato's dialogue "Cratylus" is devoted to the etymology of the god's name, in which Socrates is arguing for a folk etymology not from "unseen" but from "his knowledge ("eidenai") of all noble things". Modern linguists have
Orcus Orcus Orcus () was a god of the underworld, punisher of broken oaths in Italic and Roman mythology. As with Hades, the name of the god was also used for the underworld itself. In the later tradition, he was conflated with Dis Pater. Orcus was portrayed in paintings in Etruscan tombs as a hairy, bearded giant. A temple to Orcus may have existed on the Palatine Hill in Rome. It is likely that he was transliterated from the Greek daemon Horkos, the personification of Oaths and a son of Eris. The origins of Orcus may have lain in Etruscan religion.