disease of the skin, skin condition, skin disease, skin disorder, skin problem - a disease affecting the skin

lichen planus, lichen ruber planus - an eruption of shiny flat-topped purplish (usually itchy) papules on the wrist and forearms and thighs

division Lichenes, Lichenes - comprising the lichens which grow symbiotically with algae; sometimes treated as an independent group more or less coordinate with Algae and Fungi

ascolichen - a lichen in which the fungus component is an ascomycete

basidiolichen - a lichen in which the fungus component is a basidiomycete

lecanora - any lichen of the genus Lecanora; some used in dyeing; some used for food

roccella, Roccella tinctoria - a source of the dye archil and of litmus

beard lichen, beard moss, Usnea barbata - greenish gray pendulous lichen growing on trees

horsehair lichen, horsetail lichen - any of several lichens of the genus Alectoria having a thallus consisting of filaments resembling hair

arctic moss, Cladonia rangiferina, reindeer lichen, reindeer moss - an erect grayish branching lichen of Arctic and even some north temperate regions constituting the chief food for reindeer and caribou and sometimes being eaten by humans

crotal, crottal, crottle - any of several lichens of the genus Parmelia from which reddish brown or purple dyes are made

Cetraria islandica, Iceland lichen, Iceland moss - lichen with branched flattened partly erect thallus that grows in mountainous and arctic regions; used as a medicine or food for humans and livestock; a source of glycerol

fungus - a parasitic plant lacking chlorophyll and leaves and true stems and roots and reproducing by spores