Discussion of accentuation and declension of proper names in -ῶν (Ξενοφῶν, Κτησιφῶν, Δημοφῶν, Ἀντιφῶν, Τυφῶν, ταῶν) focusing on Ποσειδῶν: whether it is recessive or oxytone, morphological division, case endings, vocative forms, dialectal variants, and processes (division, cline, elision, vocative, dialectal development, synaeresis).
περισπᾶται, Ξενοφῶν, Ἱπποκῶν, Δημοφῶν, Ἀντιφῶν, ἀμνοκῶν. σεσημείωται τὸ Ποσειδῶν καὶ ταῶν καὶ Τυφῶν περισπώμενα μέν, οὐ μέντοι διὰ τοῦ 'ντ' κλινόμενα. καὶ τὸ μὲν Ποσειδῶν ἔχει τοιαύτην ἀπολογίαν. οὐδὲν περισπώμενον εἰς 'δων' λήγει. τὸ δὲ Ποσειδῶν ἔχει τὸ 'δ' πρὸ τοῦ 'ω'. τῶν μὲν εἰς 'ων' περισπωμένων γίνεται διαίρεσις διὰ τοῦ 'ο', τοῦ δὲ Ποσειδῶν οὐ διὰ τοῦ 'ο', ἀλλ´ ἢ διὰ τοῦ 'ε' ἢ διὰ τοῦ 'α' οἷον Ποσειδέων καὶ Ποσειδάων· οὐκ ἄρα περισπᾶται. τὰ εἰς 'ων' περισπώμενα οὐ παραλήγεται φύσει μακρᾷ οἷον Κτησιφῶν Δεξικρῶν. τὸ δὲ Ποσειδῶν φύσει μακρᾷ παραλήγεται, ὥστε οὐ περισπώμενον. οὐδὲν περισπώμενον ἀποκόπτεται κατὰ γενικὴν πτῶσιν, τὸ δὲ Ποσειδῶν ἐξεκόπη παρ´ Ἀριστίᾳ Ποσειδῶ. Πάλιν τῶν εἰς 'ων' περισπωμένων ὁμόχρονος ἡ κλητικὴ τῇ εὐθείᾳ· ὁ Ξενοφῶν ὦ Ξενοφῶν ὁ Κτησιφῶν ὦ Κτησιφῶν. τοῦ Ποσειδῶνος δὲ οὐχ ἡ αὐτὴ κλητική, ὁ Ποσειδῶν γὰρ καὶ ὦ Πόσειδον διὰ τοῦ 'ο' μικροῦ, ὥστε οὐ περισπώμενον. οὐδὲν περισπώμενον ὑπὲρ δύο συλλαβὰς τρέπει τὸ 'ω' εἰς 'α' παρ´ Αἰολεῦσιν. τὸ δὲ Ποσειδῶν ἐγένετο Ποσίδαν. οὐκ ἄρα περισπώμενον. ἰδοὺ οὖν κατὰ ἑπτὰ τρόπους καὶ κανόνας δείκνυται τὸ Ποσειδῶν μὴ περισπώμενον, λέγω δὲ ἀπὸ ληγούσης, ἀπὸ διαιρέσεως, ἀπὸ κλίσεως, ἀπὸ παραληγούσης, ἀπὸ ἀποκοπῆς, ἀπὸ κλητικῆς καὶ ἀπὸ διαλέκτου. εἰ δὲ περισπώμενον οὐκ ἔστι, δηλονότι ὀξύνεται. καὶ γὰρ εἰς 'δων' πολλὰ ὀξύτονα Χελιδών Μυρμιδών. τὰ δ´ εἰς 'δων' λήγοντα διὰ 'ο' κλίνεται, χωρὶς εἰ μὴ παραλήγοιτο τῷ 'υ' οἷον Καλυδών Ἀμυδών. εἴπερ οὖν ὀξύτονον τὸ Ποσειδῶν, ἔδει διὰ τοῦ 'ο' κλίνεσθαι. οὐ κλίνεται δέ. οὐκ ἄρα ὀξύτονον. Δῆλον οὖν, ὅτι κατὰ ταῦτα πάντα μονῆρές ἐστι τὸ ὄνομα οὔτε τοῖς ὀξυνομένοις τὴν αὐτὴν ἀκολουθίαν σῶζον οὔτε τοῖς περισπωμένοις. Ἀλλ´ ἔστιν εἰπεῖν, ὅτι Ποσειδέων παροξυτόνως παρ´ Ἴωσι λέγεται ὁ θεός. ἐκ δὲ τούτου τοῦ Ποσειδέων συνῃρέθη Ποσειδῶν. ἐκ ταύτης οὖν συναλοιφῆς δείκνυται περισπώμενον. ἡ γὰρ ὀξεῖα καὶ βαρεῖα εἰς περισπωμένην συνέρχονται. —τὸ δὲ Τυφῶν καὶ ταῶν οὐκ ἐκλίθη διὰ τοῦ 'ντ', ἐπεὶ καὶ ἑτέραν ἔσχε κατάληξιν· Τυφῶς γὰρ καὶ ταῶς διὰ τοῦ 'ς'. Τὰ εἰς 'ων' θηλυκὰ μὴ ἐπὶ πόλεων κατηγορούμενα ὀξύνεται, ὁπότε μὴ διὰ τοῦ 'ω' κλίνεται, χιών, λαγών, τρυγών, σταγών, γοργών.
Xenophon, Hippocon, Demophon, Antiphon, amnokōn are circumflexed. Poseidōn and taōn and Typhōn have been marked as circumflexed, but not, however, as being declined through -ντ-. And Poseidōn has the following defence. Nothing circumflexed ends in -δων; but Poseidōn has δ before ω. Of the circumflexed words in -ων there arises a diaeresis through ο, but of Poseidōn not through ο, but either through ε or through α, as Poseidéōn and Poseidáōn; therefore it is not circumflexed. The circumflexed words in -ων do not have a naturally long penult, as Ktēsiphōn, Dexikrōn; but Poseidōn has a naturally long penult, so that it is not circumflexed. Nothing circumflexed is apocopated in the genitive case, but Poseidōn has been apocopated in Aristias as Ποσειδῶ. Again, of the circumflexed words in -ων the vocative is of the same quantity as the nominative: ὁ Ξενοφῶν, ὦ Ξενοφῶν; ὁ Κτησιφῶν, ὦ Κτησιφῶν. But of Ποσειδῶν the vocative is not the same; for ὁ Ποσειδῶν and ὦ Πόσειδον with short ο, so that it is not circumflexed. Nothing circumflexed, when it is more than two syllables, changes ω to α among the Aeolians; but Ποσειδῶν became Ποσίδαν. Therefore it is not circumflexed. Behold then, in seven ways and by rules Poseidōn is shown not to be circumflexed—I mean from the ending, from diaeresis, from declension, from the penult, from apocope, from the vocative, and from dialect. But if it is not circumflexed, clearly it is accented with an acute. For in -δων there are many oxytone words, Χελιδών, Μυρμιδών. But the words ending in -δων are declined through ο, unless the penult is with υ, as Καλυδών, Ἀμυδών. If then Ποσειδῶν is oxytone, it ought to be declined through ο; but it is not declined so. Therefore it is not oxytone. It is clear then that in all these respects the name is exceptional, preserving neither the same sequence as the acute-accented nor as the circumflexed. But it is possible to say that among the Ionians the god is said as Poseidéōn with paroxytone accent; and from this Poseidéōn was contracted to Ποσειδῶν. From this contraction, then, it is shown to be circumflexed; for an acute and a grave come together into a circumflex.—But Typhōn and taōn were not declined through -ντ-, since they also had another ending; for Τυφῶς and ταῶς with -ς. Feminines in -ων not predicated of cities are accented with an acute, whenever they are not declined through ω: χιών, λαγών, τρυγών, σταγών, γοργών.