Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
1. pēro, ōnis, m., a kind of boot made of raw hide, worn chiefly by soldiers and wagoners (cf. caliga): crudus, Verg. A. 7, 690: alto per glaciem perone tegi, Juv. 14, 186; App. M. 7, p. 465; Sid. Ep. 4, 20: perones effeminati, Tert. Pall. 5.
2. Pērō, ōnis, f., = Πηρώ, the daughter of Neleus and wife of Bias, Prop. 2, 4, 9 (2, 3, 53).