bŏnāsus

i, m.
I. a species of bull in Pœonia, with the hair of a horse, and with horns unfit for fighting, hence saving itself by flight, Plin. 8, 15, 16, § 40; Sol. 40; cf. Aristot. H. A. 9, 45.
Lewis & Short
A Latin Dictionary, 1879
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