υ Υ, υ, ὐψιλόντό, indecl., twentieth letter of Gr. alphabet: as numeral υʹ 400, but ͵υ 400, 000. Called ὑψιλόν, because the orig. sound was broad, like ου, and afterwards was thin like French u. The Gr. υ, like Lat. v, was originally both a vowel (u) and a semi-vowel (v), v. infr. II. Interchanges of υ with other vowels, Aeolic for ο, as ὄνυμα στύμα ὔρνις for ὄνομα στόμα ὄρνις; also πίσυρες for πέτορες (τέσσαρες) , cf. νύξ, Lat. nox. Aeolic, the diphth. ου became οι, Μοῖσα for Μοῦσα, λέγοισα for λέγουσα. ῡ sometimes replaces οι, as κοινός ξυνός, κοίρανος κύριος. Boeot. ῡ for ω, as χελύνη for χελώνη. υ as a semivowel represented vau (v) , the digamma, sometimes it formed the diphth. αυ, as αὐέρυσαν for ἀνϝέρυσαν (v. αὐερύω) , αὐίαχοι for ἀνϝίαχοι, αὐάτα for αϝάτα (ἄτη) , καλαῦροψ for καλάϝροψ, ταλαύρινος for ταλάϝρινος, ταναύποδες for ταναϝόποδες; sometimes the dipth. ευ, as εὔαδεν for ἔϝαδεν.