Charlton T. Lewis, Charles Short, "A Latin Dictionary" (1879):
cassis , ĭdis (access. form cassĭda , ae, like chlamyda from chlamys, Prop. 3 (4), 11, 15; Verg. A. 11, 775; cf. Prob. II. p. 1473 P. Lind.; Charis. p. 80 P.; Prisc. p. 698 ib. Also Paul. ex Fest. p. 48, instead of cassilam, the...