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Webster 1913 Edition
Pityriasis
‖
Pitˊy-ri′a-sis
,Noun.
[NL., fr. Gr. [GREEK], fr. [GREEK], lit., bran.]
1.
(Med.)
A superficial affection of the skin, characterized by irregular patches of thin scales which are shed in branlike particles.
‖Pityriasis versicolor
[NL.]
(Med.)
, a parasitic disease of the skin, characterized by the development of reddish or brownish patches.