Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Hylas, ae, m., = Ὕλας, a beautiful youth of Œchalia (or Argos), companion of Hercules in the Argonautic expedition, who was carried off by the nymphs, and long sought for by Hercules in vain, Prop. 1, 20, 6; Ov. A. A. 2, 110; Juv. 1, 164; Val. Fl. 3, 596; Hyg. Fab. 14; Verg. E. 6, 44 (where, by poet. license, the voc. is scanned Hylā, Hȳl’, like the Gr. Ἆρες, Ἄρες, Mart. 9, 11, 15).
† hȳlē, ēs, f., = ὕλη (wood; hence), stuff, materials, matter, Attei. ap. Suet. Gramm. 10; Macr. S. 1, 17 fin.
Hȳles, ae, m., a centaur, Ov. M. 12, 378.