Wordnet 3.0
NOUN (1)
1.
a chronic skin disease characterized by dry red patches covered with scales;
occurs especially on the scalp and ears and genitalia and the skin over bony prominences;
The Collaborative International Dictionary of English v.0.48:
Psoriasis \Pso*ri"a*sis\, n. [NL., fr. Gr. ?, fr. ? psora.]
(Med.)
(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.
[1913 Webster]
WordNet (r) 3.0 (2006):
psoriasis
n 1: a chronic skin disease characterized by dry red patches
covered with scales; occurs especially on the scalp and
ears and genitalia and the skin over bony prominences