Lewis & Short

2. Tī̆gris, ĭdis, m., = Τίγρις, the river Tigris (qs. arrowy, so called from its rapidity), Varr. L. L. 5, § 100 Müll.; Mel. 1, 11, 2; 3, 8, 32; Plin. 6, 27, 31, § 127; Hor. C. 4, 14, 46; Luc. 3, 256; 3, 261 sq.; 8, 370; Curt. 4, 9, 16; Sen. Herc. Fur. 1324.