HyperDic

English > 2 senses of the word will-o'-the-wisp:
NOUNphenomenonwill-o'-the-wisp, friar's lantern, ignis fatuus, jack-o'-lanterna pale light sometimes seen at night over marshy ground
cognitionwill-o'-the-wisp, ignis fatuusan illusion that misleads
English > will-o'-the-wisp: 2 senses > noun 1, phenomenon
MeaningA pale light sometimes seen at night over marshy ground.
Synonymsfriar's lantern, ignis fatuus, jack-o'-lantern
Broaderlight, visible light, visible radiation(physics) electromagnetic radiation that can produce a visual sensation
English > will-o'-the-wisp: 2 senses > noun 2, cognition
MeaningAn illusion that misleads.
Synonymignis fatuus
Broaderillusion, fantasy, phantasy, fancySomething many people believe that is false / false