1.(Biol.) A large orange-colored luminescent mushroom, Clitocybe illudens, also classified as Omphalotus olearius. It is poisonous and is sometimes found on hardwood tree stumps.
2.A pale light sometimes seen at night over marshy ground; an ignis fatuus; a will-o'-the-wisp. "(Newspaper speculations) supplying so many more jack-o'-lanterns to the future historian."
3.A lantern carved from a hollowed-out pumpkin, with holes cut in the rind and so shaped that when it is illuminated by a candle inside, the features of a human face, cat's face, etc. appear in a glowing yellow color. It is used mostly as a decoration at Halloween.
