arrūgĭa

ae, f.

akin to runco, runcina, ὀρύσσω, ὀρύξω, to dig; cf. Corssen, Ausspr. I. p. 543; v. corrugus

I. a shaft and pit in a gold-mine, Plin. 33, 4, 21, § 70.
Lewis & Short
A Latin Dictionary, 1879
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