Definify.com

Webster 1913 Edition


Lichen

Li′chen

(lī′kĕn; 277)
,
Noun.
[L., fr. Gr.
λειχήν
.]
1.
(Bot.)
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
.
☞ A favorite modern theory of lichens (called after its inventor the Schwendener hypothesis), is that they are not autonomous plants, but that they consist of ascigerous fungi, parasitic on algæ. Each lichen is composed of white filaments and green, or greenish, rounded cells, and it is argued that the two are of different nature, the one living at the expense of the other. See
Hyphæ
, and
Gonidia
.
2.
(Med.)
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.

Webster 1828 Edition


Lichen

LICH'EN

,
Noun.
[L. from Gr.]
1.
In botany, the name for an extensive division of cryptogamian plants, constituting a genus in the order of Algae, in the Linnean system, but now forming a distinct natural order. They appear in the form of thin flat crust, covering rocks and the bark of trees, or in foliaceous expansions, or branched like a shrub in miniature, or sometimes only as a gelatinous mass, or a powdery substance. They are called rock moss and tree moss, and some of the liverworts are of this order. They also include the Iceland moss and the reindeer moss; but they are entirely distinct from the true mosses (Musci.)
2.
In surgery, a species of impetigo, appearing in the form of a red, dry, rough, and somewhat prurient spot, that gives off small furfuraceous scales.

Definition 2024


lichen

lichen

English

Lichen growing on a rock.

Noun

lichen (plural lichens)

  1. Any of many symbiotic organisms, being associations of fungi and algae; often found as white or yellow patches on old walls, etc.
    • 1894Rudyard Kipling, The Jungle Book, Lukannon
      The Beaches of Lukannon–the winter wheat so tall–
      The dripping, crinkled lichens, and the sea-fog drenching all!
    • 1895H. G. Wells, The Time Machine, ch XI
      It was the same rich green that one sees on forest moss or on the lichen in caves: plants which like these grow in a perpetual twilight.
    • 1915John Muir, Travels in Alaska, ch V
      The nibble marks of the stone adze were still visible, though crusted over with scale lichens in most places.
  2. (figuratively) Something which spreads across something else, causing damage.
    • 1912, Zane Grey, Riders of the Purple Sage, Chapter 15
      Meanwhile, abiding a day of judgment, she fought ceaselessly to deny the bitter drops in her cup, to tear back the slow, the intangibly slow growth of a hot, corrosive lichen eating into her heart.

Synonyms

  • (something which spreads): cancer

Derived terms

Translations

See also

References

  1. 1 2 lichen” in Merriam-Webster Online Dictionary, Merriam-Webster Online.
  2. 1 2 lichen in Cambridge English Dictionary
  3. 1 2 lichen” (US) / “lichen” (UK) in Oxford Dictionaries, Oxford University Press.

French

Etymology

Borrowed from Latin lichen, from Ancient Greek λειχήν (leikhḗn).

Pronunciation

  • IPA(key): /likɛn/

Noun

lichen m (plural lichens)

  1. lichen

Derived terms

  • lichénique

Anagrams


Latin

Etymology

Borrowing from Ancient Greek λειχήν (leikhḗn)

Pronunciation

Noun

līchēn m (genitive līchēnos or līchēnis); third declension

  1. (literally) a cryptogamic species of vegetation growing on trees, lichen
  2. (transferred sense, medicine) an eruption on the skin of men and beasts, a tetter, ringworm
    1. (and especially) a callous excrescence upon the leg of a horse, used as a medicine

Declension

This noun needs an inflection-table template.

Derived terms

Related terms

  • līchēna
  • līchēnicos

Descendants

References