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Rŭbĭco (nom. Rubicon, Luc. 1, 214 Cort. N. cr.), ōnis, m., a small river on the east coast of Italy, which formed the boundary between Italy and Cisalpine Gaul; celebrated for having been crossed by Cœsar at the breaking out of the civil war; prob. the modern Pisatello, Plin. 3, 15, 20, § 115; Cic. Phil. 6, 3, 5; Suet. Caes. 31; Luc. 1, 214.