Eä

Quenya: Imperative of to be, literally let it be

The World, the Universe in Elven cosmology. The realisation of the Music of the Ainur which begun to exist when the Creator said "Eä", hence considered by Elves its name. It comprises Arda, the heavens and is animated by the SecretFire, bound by the priciples of space, time and matter. Outside Eä are the TimelessHalls and the Void.

Tolkien considered in a personal text the notion that other planets apart Arda (Earth) could exist in Eä but there would be no way for the Eruhíni to know about it.