noun
or jack-a-lantern also jack-o'-lanthorn ˈjakəˌ ̷ ̷ ̷ ̷ ; or jack-with-a-lantern ˈ ̷ ̷ ̷ ̷ ̷ ̷ˌ ̷ ̷ ̷ ̷
1.
a. obsolete : a man carrying a lantern : a night watchman
b. : ignis fatuus
c. : saint elmo's fire
d. : a lantern made of a pumpkin or other vegetable so prepared as to show in illumination features of a human face
2. : a large luminescent mushroom ( Clitocybe illudens )