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Tăgus, i, m., a river in Lusitania, celebrated for its golden sands, now Tajo or Tagus, Liv. 21, 5, 8; Mel. 3, 1, 6; Plin. 4, 22, 35, § 115; Ov. Am. 1, 15, 34; id. M. 2, 251; Luc. 7, 755; Sil. 1, 155; 16, 559; Mart. 1, 50, 15; 10, 96, 3.