ignis fatuus

noun
ig·​nis fat·​u·​us | \ ˈig-nəs-ˈfa-chə-wəs How to pronounce ignis fatuus (audio) , -ˈfach-wəs \
plural ignes fatui\ ˈig-​ˌnēz-​ˈfa-​chə-​ˌwī How to pronounce ignes fatui (audio) \

Definition of ignis fatuus

1 : a light that sometimes appears in the night over marshy ground and is often attributable to the combustion of gas from decomposed organic matter
2 : a deceptive goal or hope

First Known Use of ignis fatuus

1563, in the meaning defined at sense 1

History and Etymology for ignis fatuus

Medieval Latin, literally, foolish fire

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The first known use of ignis fatuus was in 1563

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Cite this Entry

“Ignis fatuus.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/ignis%20fatuus. Accessed 25 January 2020.

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Britannica.com: Encyclopedia article about ignis fatuus

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