κερᾱτο-ειδής · kerato-eidēs — LSJ
like horn, χιτών external coat of the eye, Cels. 7.7.13, Poll. 2.70, Aët. 7.1, etc.
applied to a part of the coat, opp. λευκός, Ruf. Onom. 27, cf. Gal. UP 10.3 (distinguishing cornea from sclera).
horn-shaped, λοβοί Dsc. 2.158; γωνίαι J. BJ 5.5.6; μορφή Sch. Arat. 779.
sounding like a horn, ἦχοι D.H. Comp. 14.