This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
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n. A fungus, usually of the class Ascomycetes, that grows symbiotically with algae, resulting in a composite organism that characteristically forms a crustlike or branching growth on rocks or tree trunks.

n. Pathology Any of various skin diseases characterized by patchy eruptions of small, firm papules.

v. To cover with lichens.

n. Any of many symbiotic organisms, being associations of fungi and algae; often found as white or yellow patches on old walls, etc.

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.

n. 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.

n. In botany, a plant or vegetable growth of the group Lichenes, ordinarily recognizable by its dry aspect and gray, brown, greenish, or blackish color, and its appearance in crusts, scaly patches, or bush-like forms on trees, rails, rocks, etc.

n. In pathology, an eruption of papules, of a red or pale color, which do not reach a vesicular or pustular stage. They may be in clusters or scattered, or disseminated over the surface of the skin; and may be attended with itching, as in lichen ruber, or may be quite free from it, as in lichen scrofulosorum.

To lichenize.

n. any of several eruptive skin diseases characterized by hard thick lesions grouped together and resembling lichens growing on rocks

n. any thallophytic plant of the division Lichenes; occur as crusty patches or bushy growths on tree trunks or rocks or bare ground etc.

"I love old graveyards, especially when the stones are weathered and covered in lichen or ivy."

lichens   

horsetail lichen    crab's-eye lichen    yellow wall-lichen    wild lichen    foliaceous lichen   

reindeer moss    Iceland moss    lichen planus    moss    fungus    lichened    algae   

lichenes    rock moss    tree moss   

Steichen    liken   

moss    algae    fungus    brushwood    fern    seaweed    herbage    twig    ivy    furze