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Medical Dictionary

lichen

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noun li·chen \ˈlī-kən\

Medical Definition of lichen

  1. 1:  any of several skin diseases characterized by the eruption of flat papules; especially :  lichen planus

  2. 2:  any of numerous complex plantlike organisms made up of an alga and a fungus growing in symbiotic association on a solid surface (as a rock)





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