Lewis & Short

sub-lŭo, no perf., lūtum, ĕre, v. a., to wash or bathe underneath (very rare; not in Cic.).

  1. I. Lit.: aliquid aquā calidā, Cels. 4, 15; Col. 6, 32, 1: inguina, Mart. 6, 81, 2: subluto podice, id. 2, 42, 1.
  2. II. Transf., of rivers, to flow along the base of, to wash the foot of: hunc montem flumen subluebat, Caes. B. C. 3, 97: radices collis (flumina), id. B. G. 7, 69.
    Pass.: Asia, quā Hellesponto, quā rubro mari subluitur, Curt. 9, 6, 20.