Prŏcўon

ōnis, m.
I. a constellation that rises before the dog-star (pure Lat. Antecanis), Cic. Arat. 222; Hor. C. 3, 29, 18; Cic. N. D. 2, 44, 144; Col. 11, 2, 52; Manil. 5, 197.
Lewis & Short
A Latin Dictionary, 1879
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