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urvum (urbum), i, n., the curved part of a plough, the plough-tail, with which the bounds of cities were marked out, Varr. R. R. 2, 1, 10 Schneid. N. cr.; cf. id. L. L. 5, §§ 127 and 135 Müll.; Dig. 50, 16, 239, § 6.