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jăcŭlus, a, um, adj. [jacio], that is thrown (mostly subst.). So, rete jaculum and simply jaculum, a casting-net, fishingnet, Plaut. Truc. 1, 1, 14; id. As. 1, 1, 86; cf.: hi jaculo pisces, illi capiuntur ab hamis, Ov. A. A. 1, 763.
Also of the net of the gladiator retiarius, Isid. Orig. 18, 54.
Hence, subst.: jăcùlus, i, m.