Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
2. Sĭnon, ōnis, m., son of Æsimus, through whose perfidy the Trojans were induced to take the wooden horse within their city, Verg. A. 2, 79 sq.; Hyg. Fab. 108; Dict. Cret. 5, 12; Plin. 7, 56, 57, § 202.