Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
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.