Lewis & Short

salsūgo (collat. form salsĭlāgo, Plin. 31, 7, 42, § 92; 18, 12, 32, § 124), ĭnis, f. [salsus],

  1. I. saltness, brackishness, Vitr. 1, 4; Plin. 36, 23, 55, § 176; 19, 5, 26, § 84 al.: terra salsuginis, i. e. a desert, Vulg. Job, 39, 6; id. Jer. 17, 6.
  2. II. Transf., salt-water, brine, Plin. 19, 5, 26, § 85; 31, 7, 42, § 92.