lichen

[ lahy-kuhn ]

noun

1. any complex organism of the group Lichenes, composed of a fungus in symbiotic union with an alga and having a greenish, gray, yellow, brown, or blackish thallus that grows in leaflike, crustlike, or branching forms on rocks, trees, etc.
2. Pathology. any of various eruptive skin diseases.

verb (used with object)

1. to cover with or as if with lichens.

lichen

/ ˈlɪtʃən; ˈlaɪkən /

noun

1. an organism that is formed by the symbiotic association of a fungus and an alga or cyanobacterium and occurs as crusty patches or bushy growths on tree trunks, bare ground, etc. Lichens are now classified as a phylum of fungi ( Mycophycophyta )
2. pathol any of various eruptive disorders of the skin

lichen

/ lī′kən /

1. The mutualistic symbiotic association of a fungus with an alga or a cyanobacterium, or both. The fungal component of a lichen absorbs water and nutrients from the surroundings and provides a suitable environment for the alga or cyanobacterium. These live protected among the dense fungal hyphae and produce carbohydrates for the fungus by photosynthesis. Owing to this partnership, lichens can thrive in harsh environments such as mountaintops and polar regions. The more familiar lichens grow slowly as crusty patches, but lichens are found in a variety of forms, such as the tall, plantlike reindeer moss. The association between the different organisms in a lichen is so close that lichens are routinely referred to as a single organism, and scientists classify lichens using the name of the fungal component.

Derived Forms

• ˈlichenˌoid, adjective
• ˈlichened, adjective
• ˈlichenous, adjective
• ˈlichen-ˌlike, adjective

Other Words From

• lichen·i·zation noun
• lichen·like adjective
• un·lichened adjective

Word History and Origins

Origin of lichen¹

1595–1605; < Latin līchēn < Greek leichḗn

Word History and Origins

Origin of lichen¹

C17: via Latin from Greek leikhēn, from leikhein to lick

Example Sentences

“If I were to make a prediction, I would envisage a growing fraction of the Peninsula’s landscape becoming dominated by a mosaic ecosystem of mosses, lichens, liverworts and fungi,” Roland said.

From Salon

"All the letters have been repainted by hand. We wanted to protect the lichen and to make sure the stone was still in keeping with the surroundings."

From BBC

Functional for the outdoors, jackets are cut from cotton gabardine, wool and cashmere for warmth, while the Burberry Check is reworked in earthy colorways like sand and lichen.

From Los Angeles Times

“A rich garden of life has grown on the megaliths, an exceptional lichen garden has grown. So it’s potentially quite concerning.”

From BBC

The stones are covered in more than fifty different lichens, some of them rare.

From BBC