Lewis & Short

Ătū̆rus (on account of the length of the u, sometimes written Aturrus; cf. Arabia; once ŭ, Luc. 1, 420), i, m., = Ἀτούριος, a river in Aquitania, now Adour, Aus. Parent. 4, 11; id. Mos. 468; cf. Mann. Gall. p. 116.