Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Sīla, ae, f., a large forest in the country of the Bruttii, which yielded great quantities of pitch, Cic. Brut. 22, 85; Sall. Fragm. ap. Serv. Verg. A. 12, 715 (H. 4, 7 Dietsch); Plin. 3, 5, 10, § 74; Verg. G. 3, 219; id. A. 12, 715.
Hence, Sīlānus, a, um, adj., of or belonging to the forest of Sila: caseus, Cassiod. Var. 12, 12.
silaus, i, m., a kind of parsley, smallage: Apium graveolens, Linn.; Plin. 26, 8, 56, § 88.
1. sĭlus, a, um, adj., having a broad, turned-up nose, pug-nosed, snub-nosed, σιμός (cf. simus): ecquos (deos arbitramur) silos, flaccos, frontones? etc., Cic. N. D. 1, 29, 80; ante-class. collat. form sīlo, ōnis, m., Plaut. Rud. 2, 2, 11; Varr. ap. Non. 25, 25.