Definition of jack o' lantern in English English dictionary
(deyim) 1. Ignis fatuus. 2. a lantern made of a pumpkin cut to look like a human face 3. a large orangish gill fungus (Omphalotus olearius syn. Clitocybe illudens) that is poisonous and luminescent
pumpkin whose top and stalk are cut out and the inner part removed and then the outer shell is carved in a decorative manner (usually it is illuminated from within by a candle and used for Halloween)
A carved pumpkin whose top and stem have been cut out and interior removed, leaving a hollow shell that is then decorated to represent a face, illuminated from within by a candle