the GNU version of the Collaborative International Dictionary of English
n. A tough, horny animal substance entering into the composition of the skeleton of sponges, and other invertebrates; -- called also keratode.
adj. Containing hornlike fibers or fibers of keratose; belonging to the Keratosa.
Word Usage
"Oscar Schmidt has already pointed this out in the siliceous sponges and keratose sponges; and I, in my monograph, in three volumes, on the Calcareous"