scleroid

adj

1. Having a hard texture.

   “The shells of nuts are scleroid.”

   “This scleroid form , which plays a very important part in the vegetation of Fungi, is only a transitory one; it always proceeds from the filamentous state, and may be compared with the tubers of the Potato, and not with a true subterranean stem; its life is truly latent, and only preserved by the hygrometric nature of its tissue.”

   “The scleroid patches, when present, took no part in the reaction. No new scleroid tissue was produced.”

   “The walls of these scleroid basidia often reach 1 μm or more in thickness and the walls stain deeply with congo red.”

2. thickened.

   “Did you find his drums were thickened and scleroid ?”

   “Pharyngeal walls thick, scleroid.”

noun

1. The outermost layer of an eyeball.

   “This is caused by the scleroid which turns around the optic nerve, and projects somewhat above it, thus forming, when illuminated, the clear scleroidal margin.”

   “Bone had been found in various organs and tissues, including the dura and pia mater, in the scleroid and choroid, in the tonsils, in the thyroid, the lung and pleura and other serous membranes.”

   “The scleroid is a complete sphere; choroid and retina are incomplete externally.”

2. A plant cell with thick cell walls.

   “At the end of gall formation isolated scleroids are differentiated in the gall parenchyma, and much more rarely, tracheids and vessels.”

   “Clusters of irregularly shaped cells (scleroids) form hard shells , like those of pecans or fruit pits .”

   “Scleroids form hard layers in roots, stems and seeds.”