Lewis & Short

cānesco. ĕre, v. inch. n. [caneo]. to grow white, whiten.

  1. I. Lit., to become gray or hoary: pabula canescunt (sc. calore), Ov. M. 2, 212; Plin. 31, 10, 46, § 106: canescant aequora remis, Ov. H. 3, 65: canescunt tecta, id. Am. 1, 8, 52; Col. 3, 2, 12: capilli canescunt, Plin. 30, 15, 46, § 134; 7, 2, 2, § 23: in cujus (Minervae) aede ignes numquam canescunt in favillas, Sol. 22, 18.
  2. II. Transf., = senescere, to grow old, Ov. M. 9, 422: eaque (quercus) canescet saeclis innumerabilibus, Cic. Leg. 1, 1, 2.
    Trop., of discourse: cum ipsa oratio jam nostra canesceret, was getting feeble, Cic. Brut. 2, 8; cf. Quint. 11, 1, 31; Petr. 2, 8.