Lewis & Short

in-cānesco, canŭi, 3, v. inch. n., to become white, to turn gray or hoary (poet.): tortaque remigio spumis incanuit unda, Cat. 63, 13: ornusque incanuit albo Flore piri, Verg. G. 2, 71: gelu magnoque incanuit imbre Caucasus, Val. Fl. 6, 611: cum pigra incanuit aetas, Sil. 3, 328.