F0141100 (fûr′mə-mənt)n. The vault or expanse of the heavens; the sky.[Middle English, from Old French, from Late Latin firmāmentum, from Latin, support, from firmāre, to strengthen; see firm2.]fir′ma·ment′al(-mĕn′tl) adj.Thesaurus
Adj.
1.
firmamental - relating to the firmament or upper regions