רקיע
'reqiy' is traditionally translated as “firmament”, essentially a made up word borrowed and tweaked from the Latin for “pillar” but with no real meaning other than within the text.
The word appears only 17 times, nine of which occur in the first chapter of Genesis. Half of the Genesis instances occur within the phrase 'reqiy hebedil bin' which seems to indicate a distribution of knowledge.
Its other instances occur only in Psalms, Daniel, and Ezekiel, and frankly, each is weirder than the last.
Psalms 19:1 relates 'reqiy' to the Semim and a kebed. Psalm 150:1 appears to present Ihoh bragging of the power of 'reqiy'.
Daniel 12:3 appears to speak of the wisdom of “the star people beyond”.
The Ezekiel references all occur within chapter 1 and 10, in which Ezekiel describes a flying metal craft and associated with the kerobim.