Lewis & Short

rĕgressĭo, ōnis, f. [regredior], a going back, return; a retiring, retreat (postAug.).

  1. I. Lit.: maturata, App. M. 2, p. 122, 39: vespertina, id. ib. 9, p. 227, 17: non incruenta, Front. Princ. Hist.
  2. II. Trop., a fig. of rhetoric, repetition, the Gr. ἐπάνοδος, Quint. 9, 3, 35; Rufin. Schem. Lex. 19 (p. 252 Frotsch.).