cōrўcus

i, m.
I. a leathern sack filled with sand, flour, etc., by means of which the athletae exercised in the palæstra; only fig.: corycus laterum et vocis meae Bestia, Cic. Phil. 13, 12, 26 B. and K., Halm; cf. Klotz and Orell. ad loc.
Lewis & Short
A Latin Dictionary, 1879
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