Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Lĕarchus, i, m., = Λέαρχος,
- I. the son of Athamas and Ino, whom Athamas, in a fit of madness, killed, Ov. M. 4, 515; id. F. 6, 479; Hyg. Fab. 1, 2.
Hence,
- II. Lĕar-chēus, a, um, adj., of Learchus: umbrae, Ov. F. 6, 491.