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Definition of "lichen" []

  • 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. (noun)
  • Pathology Any of various skin diseases characterized by patchy eruptions of small, firm papules. (noun)
  • To cover with lichens. (verb-transitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "lichen" in a sentence
  • "I love old graveyards, especially when the stones are weathered and covered in lichen or ivy."
  • "But not before I've admired the extra-large version of your picture, and admired the way the lichen is growing in the bottoms of the incised letters."
  • "How could we even consider trusting blokes who look as though the triffid like lichen from the last cave they lived has taken root in their heart?"