英语释义
1. any of numerous complex plantlike organisms made up of an alga or a cyanobacterium and a fungus growing in symbiotic association on a solid surface (such as on a rock or the bark of trees) Note: The main body of the lichen, known as the thallus, is formed by fungal filaments which surround the photosynthetic algal or cyanobacterial cells. The lichen is usually described as having a leaflike (foliose), crusty (crustose), or branching shrub-like (fruticose) form. Lichens often play an important part in the weathering of rocks and include some that are sources of natural dyes.
2. any of several skin diseases characterized by the eruptions of flat papules
3. a type of small plant that grows on rocks and walls
4. a plantlike organism made up of an alga and a fungus growing together
5. any of several skin diseases characterized by the eruption of flat papules especially lichen planus
6. 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)