Definition of: hypethral

(hi·pē′thrəl, hī-) adjective
Roofless, as a building open to the sky: said of a building whose roof has been destroyed or never completed, or of a sanctuary, etc., never intended to be roofed. Also spelled hypaethral. [<L hypaethrus <Gk. hypaithros <hypo- under + aithēr ether, clear sky]