lăcūnar

āris
I. gen. plur. lacunariorum for lacunarium, Vitr. 4, 3, 1 al.; dat. plur. lacunariis, id. 5, 2), n. lacuna, a wainscoted and gilded ceiling of an unvaulted chamber, a panel-ceiling, a ceiling (so called from its sunken spaces; class.), Vitr. 7, 2: non ebur neque aureum Mea renidet in domo lacunar, Hor. C. 2, 18, 2: gladium e lacunari seta equina aptum demitti jussit, Cic. Tusc. 5, 21, 62: primus lacunaria pingere instituit (Polygnotus), Plin. 35, 11, 40, § 124.—Prov.: spectare lacunar, Juv. 1, 56.—
II. Plur.: lăcūnārĭa, ōrum (-arium, App. Flor. 18, p. 83), n., panels of the under surface of a cornice, Vitr. 4, 3, 1; 7, 2, 2; 5, 2, 1; Plin. 35, 11, 40, § 124.
Lewis & Short
A Latin Dictionary, 1879
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