lichen

noun
li·​chen | \ ˈlī-kən How to pronounce lichen (audio) , British also ˈli-chən \

Definition of lichen

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

Illustration of lichen

Illustration of lichen

lichen 1

Other Words from lichen

lichened \ ˈlī-​kənd How to pronounce lichen (audio) , British also  ˈli-​chənd \ adjective
lichenous \ ˈlī-​kə-​nəs How to pronounce lichen (audio) , British also  ˈli-​chə-​ \ adjective

Examples of lichen in a Sentence

Recent Examples on the Web Caribou in the Delta herd and Macomb herd, which utilize lichen in the black spruce forests, have been forced to move to areas with lesser-quality feed. John Schandelmeier, Anchorage Daily News, 12 Feb. 2022 That allowed Nelson and his team to estimate how quickly the algae—and in turn, the lichen—adapted to past changes in their environment. Corryn Wetzel, Smithsonian Magazine, 17 Feb. 2022 Hot weather isn’t good for lichen growth on the open tundra, and lichens in the Tangle Lakes area and the Maclaren Desert have not fared well in recent years. John Schandelmeier, Anchorage Daily News, 14 Sep. 2021 Some of the lichen species here are found only on old-growth trees — just one of the beautiful associations in a complex ecological system that has evolved over thousands of years. Lynda V. Mapes, Anchorage Daily News, 13 Sep. 2021 Sami reindeer herders have been taking their animals to graze on the lichen of Finland’s northerly forests for hundreds of years, but community leaders say their way of life is being threatened by a potential increase in logging. The Christian Science Monitor, 1 July 2021 In 2018, when Canada hosted, the dishes served at the summit incorporated Arctic lichen and maple leaves. Washington Post, 11 June 2021 Cross handed me a blotter dipped in oakmoss absolute, extracted from a ghostly frisée-looking frond that is actually a lichen that grows on oak trees. Noy Thrupkaew, Washington Post, 21 Apr. 2021 This lichen from Florida was just identified from historical collections through DNA barcoding. John R. Platt, Scientific American, 13 Jan. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lichen.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of lichen

circa 1657, in the meaning defined at sense 2

History and Etymology for lichen

Latin, from Greek leichēn, lichēn, from leichein to lick

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Time Traveler for lichen

Time Traveler

The first known use of lichen was circa 1657

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Dictionary Entries Near lichen

lichee

lichen

Lichenales

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Statistics for lichen

Cite this Entry

“Lichen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lichen. Accessed 25 May. 2022.

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More Definitions for lichen

lichen

noun
li·​chen | \ ˈlī-kən How to pronounce lichen (audio) \

Kids Definition of lichen

: a plantlike organism made up of an alga and a fungus growing together

lichen

noun
li·​chen | \ ˈlī-kən How to pronounce lichen (audio) \

Medical Definition of lichen

1 : any of several skin diseases characterized by the eruption of flat papules especially : lichen planus
2 : 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)

More from Merriam-Webster on lichen

Nglish: Translation of lichen for Spanish Speakers

Britannica.com: Encyclopedia article about lichen

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