Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Lampĕtĭē, ēs, f., = Λαμπετίη, a daughter of the sun-god and sister of Phaëthon, who was changed into a tree, Ov. M. 2, 349; Hyg. Fab. 154; Prop. 3, 12 (4, 11), 29.