Lewis & Short

stĭbădĭum, ii, n., = στιβάδιον, a semicircular seat or couch, Plin. Ep. 5, 6, 36; Serv. Verg. A. 1, 698; Sid. Ep. 1, 11 med.; 2, 2 med.; Mart. 14, 87 in lemm.; Inscr. Orell. 2358.