Ἴτυς
βορβόρῳ δ' ὕδωρ λαμπρὸν μιαίνων οὔποθ' εὑρήσεις ποτόν → once limpid waters are stained with mud, you'll never find a drink
English (LSJ)
υος, ὁ, Itys, son of Tereus and Procne, A.Ag.1144 (lyr.), Ar.Av.212, etc. [ῐτῠ-, but ἃ Ἴτῠν αἰὲν Ἴτῡν ὀλοφύρεται S.El.148 (lyr.), cf. Ar. l.c.]
French (Bailly abrégé)
υος (ὁ) :
Itys, fils de Térée et de Procnè.
Russian (Dvoretsky)
Ἴτυς: υος (ῐ) ὁ Итий (сын Терея и Прокны, убитый как Итал Аэдоной, своей впавшей в безумие матерью; превращенная в соловья, Прокна вечно плачет о своем сыне) Aesch., Soph.
Frisk Etymological English
υος
Grammatical information: m.
Meaning: son of Tereus and Prokne, who was changed into a nightingale (A., S., Ar.); or: arisen fron the call of the nightingale, cf. S. El. 148 (lyr.): ἅ Ἴτυν αἰεν Ἴτυν ὀλοφύρεται (on the length of the υ cf. Schulze Kl. Schr. 401); also as adj. in unclear meaning (metr. inscr. from Cappadocia; cf. Ryba Rev. de phil. 57, 113ff. and ἴτυλος below).
Derivatives: with suffix Ἴτυλος son of Zethos and Aëdon (τ 522; also H. = μόνος, ὀρφανός, νέος, ἁπαλός; Pherekyd. 124 J.); also Ίτυμονεύς (Λ 672, A. R.)?;
Origin: PG [a word of Pre-Greek origin]
Etymology: On the formation Boßhardt Die Nom. auf -ευς 97, Fraenkel Nom. ag. 1, 105 A. 1. From Ἴτυς perhaps also ἴτυξ name of a bird (Phot., Suid.); cf. ὄρτυξ, ἴυγξ etc. Fur. 180 compares ἴδυξ = ἴκτις; he separates the name Ἰτυς. The name will be Pre-Greek.