ŏpŭlus

i, f.
I. a kind of maple-tree: in arboribus, quas vocant opulos, Varr. R. R. 1, 8; Col. 5, 6, 4; 5, 7, 1 al.; Plin. 14, 1, 3, § 12.
Lewis & Short
A Latin Dictionary, 1879
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