Abnormal dryness, especially of the eye.
n. abnormal dryness of the conjunctiva, the skin, or the mucous membranes. Xerosis affecting the conjunctiva is due to changes in the membrane itself, which becomes thickened and grey in the area exposed when the eyelids are open.
n. thickening of the epidermis of the skin with exaggeration of the normal creases, thought to resemble tree bark. The cause is abnormal scratching or rubbing of the skin. It is one of the cardinal features of chronic eczema, together with erythema (flushing), pruritus (itching), and xerosis (dryness).... lichenification
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