Will-o'-the-wisp

A will-o'-the-wisp (/ˌwɪl ə ðə ˈwɪsp/), will-o'-wisp (/ˌwɪl ə ˈwɪsp/), or ignis fatuus (/ˌɪɡnᵻs ˈfætʃuəs/; Medieval Latin for "foolish fire") is an atmospheric ghost light seen by travellers at night, especially over bogs, swamps, or marshes. It resembles a flickering lamp and is said to recede if approached, drawing travellers from the safe paths. The phenomenon is known by a variety of names, including jack-o'-lantern, friar's lantern, hinkypunk, and hobby lantern in Englishfolk belief, and is well attested in English folklore and in much of European folklore.