What is (a) The state of being affected with psora. [Obs.] (b) A cutaneous disease, characterized by imbricated silvery scales, affecting only the superficial layers of the skin called?

psoriasis — (a) The state of being affected with psora. [Obs.] (b) A cutaneous disease, characterized by imbricated silvery scales, affecting only the superficial layers of the skin. (Webster's 1913.)

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