Firmament

Firmament called (from the Latin firmamentum " fasteners "), even the heavens or the firmament, :

In the Babylonian world view ( and in the biblical world view that is based on ) a subdivision, the (comparable to a giant glass bell) the airspace of the world separated from the overlying " abyss ". In the German Bible with "Fixed " translated.
In a geocentric universe the world ( earth ) surrounding the rotating sphere, or a set of concentric spheres to which the celestial bodies, in particular the fixed stars ( sphere of fixed stars ), " attached " are.
That of the Earth (or other planets) visible from the sky.
The celestial sphere, an imaginary infinitely distant spherical shell around the Earth.