Lacûnar, pen. pro. lacuoâris, pen. pro. n. g. Diminutiuum Lacus. Suet. A beame in an house: a space, or separation: some haue taken it for such a beame as hangeth with candelles in marchants halles.Fulgentem gladium è lacunari demitri iussit.Cic.Aureum lacunar. Hor.
Lewis and Short: Latin dictionary
lăcūnar, āris (nom. lacūnārĭum, Isid. Orig. 15, 8, 6; 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,
to gaze at the ceiling, to be wilfully blind
, 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.