rare1. Short for IGNIS FATUUS.

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a. 1668.  Denham, The Progress of Learning, 159.

        And when that flame finds combustible earth,
Thence fatuus fires and meteors take their birth.

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1820.  A. Cottle, Expostulatory Epistle to Lord Byron, 174, in J. Cottle, Early Recollect. (1837), I. 121.

          Were powers, to stir the passions, such as thine,
A wit so subtile, fancies so divine,
Entrusted to corrupt, and turn aside
Whoe’er may take thy fatuus for a guide?

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