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ig·nis fat·u·us(ĭg′nĭs făch′o͞o-əs)
n. pl. ig·nes fat·u·i (ĭg′nēz făch′o͞o-ī′)
1. A phosphorescent light that hovers or flits over swampy ground at night, possibly caused by spontaneous combustion of gases emitted by rotting organic matter. Also called friar's lantern, jack-o'-lantern, will-o'-the-wisp, wisp.
2. Something that misleads or deludes; an illusion.
[Medieval Latin : Latin ignis, fire + Latin fatuus, foolish.]
ignis fatuus(ˈɪɡnɪs ˈfætjʊəs)
n, pl ignes fatui (ˈɪɡniːz ˈfætjʊˌaɪ)
another name for will-o'-the-wisp
[C16: from Medieval Latin, literally: foolish fire]
ig•nis fat•u•us(ˈɪg nɪs ˈfætʃ u əs)
n., pl. ig•nes fat•u•i (ˈɪg niz ˈfætʃ uˌaɪ)
1. Also called will-o'-the-wisp. a flickering phosphorescent light seen at night chiefly over marshy ground and believed to be due to spontaneous combustion of gas from decomposed organic matter.
2. something deluding or misleading.
[1555–65; < Medieval Latin: literally, foolish fire]
A Latin phrase meaning foolish fire, used to mean a naturally produced phosphorescent light sometimes seen over swampy land at night.
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|Noun||1.||ignis fatuus - a pale light sometimes seen at night over marshy ground|
|2.||ignis fatuus - an illusion that misleads|