lichen englanniksi - Sanakirja.org (englanti-englanti)

Any of many symbiotic organisms, being associations of fungi and algae; often found as white or yellow patches on old walls, etc.
(figurative) Something which spreads across something else, causing damage.

The Beaches of Lukannon–the winter wheat so tall– The dripping, crinkled lichens, and the sea-fog drenching all!
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.
The nibble marks of the stone adze were still visible, though crusted over with scale lichens in most places.
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.

Monikko