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Mŏsa, ae, m., a river in Belgic Gaul, now the Meuse or Maas, Caes. B. G. 4, 9 fin.; 4, 10 init.; Plin. 4, 14, 28, § 100; Tac. A. 2, 6; id. H. 4, 28; 5, 23.