Wordnet Synset 09255224-n
http://lila-erc.eu/data/lexicalResources/LatinWordNet/id/LexicalConcept/09255224-n an entity of type: LexicalConcept
(astronomy) an indistinct surface feature of Mars once thought to be a system of channels; they are now believed to be an optical illusion
Wordnet Synset 09255224-n