n. an edible lichen of the genus, Umbilicaria (or, less often, the genus Gyrophora), having circular, leathery, grayto-brownish thalli found attached to certain rocks by a threadlike holdfast.
1853  [The] lichen became reduced to a soft gummy pulp, and Norman thickened the mess to his taste by putting in more snow, or more of the "tripe," as it seemed to require it.