Lewis & Short

prae-vēlo, āre, v. a., to veil or cover over; to conceal by placing before (late Lat.): flammea praevelatura pudorem, Claud. Rapt. Pros. 2, 325: praevelans fronde secures, id. VI. Cons. Honor. 647: amnem Tiberis domibus amoenis, id. Laud. Stil. 2, 189.