ignis fatuus

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

Comments on ignis fatuus

What made you want to look up ignis fatuus? Please tell us where you read or heard it (including the quote, if possible).


dull or mediocre

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