Lichen
noun, verb ·Common ·High school level
Definitions
- 1 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. countable, uncountable
"The Beaches of Lukannon–the winter wheat so tall, / The dripping, crinkled lichens, and the sea-fog drenching all!"
- 2 any thallophytic plant of the division Lichenes; occur as crusty patches or bushy growths on tree trunks or rocks or bare ground etc. wordnet
- 3 Something which gradually spreads across something else, causing damage. countable, figuratively, uncountable
"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."
- 4 any of several eruptive skin diseases characterized by hard thick lesions grouped together and resembling lichens growing on rocks wordnet
- 1 To cover with lichen. transitive
"[…] making the rocks assume the mould of age and lichening the trees with damp beauty."
Example
More examples"Caribou eat almost only lichen during the winter."
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.
Related phrases
More for "lichen"
Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.