Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Cŏtytto, ūs, f., = Κοτυττώ, the goddess of lewdness, who was originally worshipped in Thrace, later in Athens also, Juv. 2, 92.
Cŏtyttia, ōrum, n., = Κοτύττια, her festival, Hor. Epod. 17, 56; Verg. Cat. 5, 19.