Lewis Short
(adjective) : bĭfŏris, e (bĭfŏrus, a, um, Vitr. 4, 6 fin.), bis-foris.
* Having two doors or folding-doors: valvae,Ov. M. 2, 4: fenestrae,id. P. 3, 3, 5.
* Having two openings or holes, double: via (narium),App. Dogm. Plat. 1.—Poet.: ubi assuetis biforem dat tibia cantum,Verg. A. 9, 618 (bisonum, imparem, Serv.); Aus. Cent. Nupt. 27: biforis tumultus,Stat. Th. 4, 668.
Charlton T. Lewis, Charles Short, A Latin Dictionary