Illustrated Companion to the Latin Dictionary/Hypaethros
This article incorporates text from a publication now in the public domain: Rich, Anthony (1849). The illustrated companion to the Latin dictionary, and Greek lexicon. p. vi. OCLC 894670115. https://archive.org/details/illustratedcompa00rich.
HYPAETH'ROS (ὕπαιθρος). Literally, under the sky, or in the open air; whence applied to a temple, or other edifice which had no roof over the central portion of its area, so that the interior was open to the sky. Hypaethral structures were generally the largest and most magnificent of their kind; indeed, the difficulty of roofing over a very large area may be regarded as a principal motive for adopting the expedient. The great temple at Paestum affords an existing specimen of this style; but no instance was to be found in Rome when Vitruvius wrote. Vitruv. iii. 2.