Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† 1. synŏdus (in inscrr. written also SYNHODVS; v. Inscr. Orell. 2160; 2627), i, f., = σύνοδος.
† 2. synŏdūs, ontis, m., = συνόδους, a fish of the bream genus: Sparus, Linn.; Ov. Hal. 107; Plin. 37, 10, 67, § 182.