lichen
/ˈlaɪ.kən/ noun, verb
Forms lichens lichening lichened
- noun Any of many symbiotic organisms, being associations of algae and fungi, often found as white or yellow-to-blue–green patches on rocks, old walls, etc.
- noun (figurative) Something which gradually spreads across something else, causing damage.
- verb (transitive) To cover with lichen.
Synonyms
Etymology
Borrowed from Latin līchēn, from Ancient Greek λειχήν (leikhḗn), from λείχω (leíkhō, “to lick”). Originally used of liverwort; the modern sense first recorded 1715.
Webster’s 1913
- noun 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.
- noun A name given to several varieties of skin disease, esp. to one characterized by the eruption of small, conical or flat, reddish pimples, which, if unchecked, tend to spread and produce great and even fatal exhaustion.
Sources: Wiktionary · Webster’s 1913 — from the Wiktionary entry “lichen”, CC BY-SA 4.0. Details