|
|
Definition of Lichen
1. Noun. Any of several eruptive skin diseases characterized by hard thick lesions grouped together and resembling lichens growing on rocks.
Specialized synonyms: Lichen Planus, Lichen Ruber Planus
2. Noun. Any thallophytic plant of the division Lichenes; occur as crusty patches or bushy growths on tree trunks or rocks or bare ground etc..
Specialized synonyms: Ascolichen, Basidiolichen, Lecanora, Roccella, Roccella Tinctoria, Beard Lichen, Beard Moss, Usnea Barbata, Horsehair Lichen, Horsetail Lichen, Arctic Moss, Cladonia Rangiferina, Reindeer Lichen, Reindeer Moss, Crotal, Crottal, Crottle, Cetraria Islandica, Iceland Lichen, Iceland Moss
Generic synonyms: Fungus
Definition of Lichen
1. n. One of a class of cellular, flowerless plants, (technically called Lichenes), having no distinction of leaf and stem, usually of scaly, expanded, frond-like forms, but sometimes erect or pendulous and variously branched. They derive their nourishment from the air, and generate by means of spores. The species are very widely distributed, and form irregular spots or patches, usually of a greenish or yellowish color, upon rocks, trees, and various bodies, to which they adhere with great tenacity. They are often improperly called rock moss or tree moss.
Definition of Lichen
1. to cover with lichens (flowerless plants) [v -ED, -ING, -S]
Medical Definition of Lichen
1. A large group of symbiotic associations between fungi and green and occasionally blue green algae. Several genera of algae and of fungi are involved and the associations are so stable and of such varied but distinct types that the lichens have been classified into genera and species. A variety of incompatibility phenomena are often manifest between individual lichens. Confined to terrestrial habitats and often used as indicators of pollution status of the environment. This entry appears with permission from the Dictionary of Cell and Molecular Biology (11 Mar 2008)
Lexicographical Neighbors of Lichen
Other Resources:
Arabic