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Denoting the heaping up of scales seen in psoriasis, which resembles the stratification of oyster shells.
[Ostraeacea, group including the oysters]
ostraceousadjective A descriptive term referring to the indurated pearly scale appearance typically associated with psoriasis, which has been fancifully likened to an oyster shell.
ostraceous(os-trā′shŭs) [Gr. ostreion, oyster]
Shaped like an oyster shell. In psoriasis, for example, ostraceous lesions are those with a concave center.