92. Vocative. A noun used in addressing a person by his name or title has properly no case ending. Accordingly the vocative case consists in general of the simple stem.
Ζεῦ βασιλεῦ
Αἶαν (for Αἰαντ-)
διόγενες
ὦ ἄνα (for ἀνακτ-)
In Il. 1.86 Κάλχαν (vocative of Κάλχας) was read by Aristarchus, Κάλχα by Zenodotus. On the other hand in Il. 12.231 Aristarchus read Πουλυδάμα, but Zenodutos Πουλυδάμαν. The form Λαοδάμα in Od. 8.141 probably has the authority of Aristarchus.
Stems in -ο form the vocative in -ε, as φίλε ἑκυρέ. Some stems in -ᾱ(η) shorten the final vowel, as νύμφᾰ, vocative of νύμφη, and the masculine συβῶτᾰ, ἠπεροπευτᾰ́, τοξότᾰ, κυνῶπᾰ, etc. But the long vowel of the stem is used in the vocative ̔Ερμεία, Ἀτρεΐδη, ὑψαγόρη, αἰναρέτη (Il. 16.31). Feminines in -ω or -ῳ form the vocative in -οι, as Λητοῖ (Il. 21.498). Evidently -ῳ : -οι : : η: ᾰ.
The words of address, πάππα, ἄττα, τέττα, μαῖα, may be ranked as vocatives. So ἠθεῖε, as to which see the note on § 96.
Note— The nominative is used for the vocative in the case of oxytones in -ων, and all nouns in -ην (Brugmann, Grundr. ii. § 206, p. 544)