Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Percōsĭus, a, um, adj., = Περκώσιος, of or belonging to Percosius, king of Cyzicus: Percosia conjux, i. e. Clyte, wife of king Percosius, Val. Fl. 3, 10.