Aenuvion

Aenuvion is Paradise, the Higher World, the abode of the gods, the upper realm in the tripartite division of creation. Its foundation is upon the vault of heaven and it is as far above the mortal realm of Urva as the sun is above the roots of the mountains. Aenuvion is the dwelling-place of many of the gods and goddesses worshiped by mortal beings, and of the diverse lesser spirits that serve them. Just as mortals have divided the lands of Urva among many different kingdoms, so these pantheons have divided Aenuvion into their separate realms: Ulusvaati where the Thaedonu-Vaati dwell, Beshanurhanta for the Rhantaseppa, etc. 
The name Aenuvion is of archaic Tuvai origin, derived from “anuiva” (the firmament, the heavens) combined with the place name suffix -ion or -aon (denoting “that which stands upon”). An evocative translation might be “that place which stands upon the vault of heaven” or “the place built above the firmament." This name has been preserved since ancient days in Tuvai and has also been passed down into modern Chomarra, so both the Vanir-Vaati and the Rhantashans use it to refer to the abode of the gods (along with simply "paradise," which is perhaps the most usual among common people of both traditions). In Orithea and Rhydain, usage of Aenuvion long ago supplanted other old Tuvai terms like Ulthaiyu (“Abode of the Gods” or “Abode of the Holy Ones”) which are now mostly found only in antiquated texts. The Rhantashani, however, often do still use "Ultaia" (the modern Chomarra form of Ulthaiyu) interchangeably with Aenuvion. They also sometimes refer to all Aenuvion as "Beshanu", derived from the proper term for the realm of their pantheon. 
It should be born in mind that when either a Rhantashan or a Vanir-Vaati says "Aenuvion" (or paradise, Ulthaiyu, Ultaia, etc.) they are most often implicitly speaking only of the particular domain of the gods they worship, i.e. the Rhantaseppa or the Thaedonu-Vaati. Although both pantheons dwell in Aenuvion, their respective worshipers tend to think of it first and foremost as the home of their own gods. Likewise they don't often spare a thought for the Aeiur Aedris or other deities that also dwell in Aenuvion. Among the Vanir-Vaati, often only sages and scholars are acquainted with the proper names for the domain of each pantheon. A common Rhantashan might call paradise "Beshanu", from Beshanurhanta, but they are likewise probably not cognizant of a real distinction. The cynically-minded might suppose that the priests and devotees of either cult prefer to avoid dwelling on the fact their gods share Paradise with a rival pantheon, and even that the gods themselves might not relish their worshipers being reminded of the fact.
Other names: Aenuvion is known as XXXXXXXXX in the elven language; just as with humans, elves who speak of XXXXXXXX typically mean the realm of their own gods, the Aeiur Aedris, not the Upper World as a whole (even though their word, like Aenuvion, properly refers to it in general rather than to a particular portion of it).