Discussion of Greek nouns and names ending in -θος, rules of accentuation (proparoxytone vs oxytone for adjectives), and many examples of place-names, ethnonyms, rivers, mountains, and personal names ending in -θος.
Τὰ εἰς 'θος' ὑπὲρ δύο συλλαβὰς παραλήγοντα 'ι' ἢ 'υ' ἢ καὶ φύσει μακρᾷ προπαροξύνεται· εἰ δέ τι ὀξύνεται, ἐπιθετικόν ἐστιν. Λάπιθος ἀφ´ οὗ Λαπίθης, λέκιθος, ἔριθος, Μίκυθος, ἄκυθος ἡ μὴ τίκτουσα, μαμμάκυθος ὁ μωρός, Αἴνηθος ὄρος. Αἰσχύλος. Λάπηθος πόλις Κύπρου. Ἀλέξανδρος Ἐφέσιος «Βήλου δ´ αὖ Κίτιόν τε καὶ ἱμερόεσσα Λάπηθος». Πεπάρηθος νῆσος τῶν Κυκλάδων ὁμώνυμον ἔχουσα πόλιν. Σεσάρηθος πόλις Ταυλαντίνων, ὥς φησιν Ἑκαταῖος. Κάνηθος, Ὄρηθος, Σέβηθος ὄνομα ποταμοῦ. ἐπίληθος «νηπενθές τ´ ἄχολόν τε, κακῶν ἐπίληθον ἁπάντων» (Od. δ 221). Ναύαιθος ποταμὸς Ἰταλίας. Φάρβαιθος πόλις Αἰγύπτου. Κέλαιθος ἔθνος Θεσπρωτικόν. Ῥιανὸς δʹ. λέγονται καὶ Κελαιθεῖς. Δάμαιθος, Κύναιθος εἷς τῶν Λυκάονος παίδων. Ὀλίγαιθος, Σίμαιθος ὄνομα ποταμοῦ. Ἀρίαιθος. τὸ δὲ βοηθός καὶ κακηθός ὁ κακιστός ὀξύνεται. Τὰ εἰς 'θος' ὑπερδισύλλαβα ἔχοντα κατὰ τὴν παραλήγουσαν δύο σύμφωνα μὴ ὄντα ἐπιθετικὰ προπαροξύνονται, Ἐρύμανθος ὄρος καὶ ποταμός «ἢ κατὰ Τηΰγετον περιμήκετον ἢ Ἐρύμανθον» (Od. ζ 103). Ἄκανθος πόλις Θρᾴκης ἀκάνθαις πεφραγμένη, ὅθεν κέκληται, ἢ ἀπό τινος Ἀκάνθου, ὡς Μνασέας. βʹ. ἔστι καὶ ἐν Αἰγύπτῳ Ἄκανθος. γʹ. ἄλλη ἐν τῇ χερρονήσῳ περὶ τὴν Κνιδίαν. δʹ. ἔστι καὶ ἡ Ἀθαμανίας. Φάλανθος ὄρος καὶ πόλις Ἀρκαδίας. Παυσανίας ὀγδόῳ (c. 35, 9) ἀπὸ Φαλάνθου. Πύρανθος πόλις μικρὰ ἢ κώμη Κρήτης περὶ Γόρτυνα. Ψίναφθος Αἰγύπτου πολίχνιον ὡς Ἀλέξανδρος ἐν Αἰγυπτιακῶν δευτέρῳ. Μέλανθος, Λαβύρινθος, Ὑάκυνθος, Λέβινθος, Προβάλινθος
Nouns in -θος of more than two syllables, with penult containing ι or υ or even a long vowel by nature, are accented on the antepenult; but if any is accented on the penult, it is adjectival. Λάπιθος, from which Λαπίθης; λέκιθος; ἔριθος; Μίκυθος; ἄκυθος, ‘the one that does not give birth’; μαμμάκυθος, ‘the fool’; Αἴνηθος, a mountain. Αἰσχύλος. Λάπηθος, a city of Cyprus. Alexander of Ephesus: “and again of Belus, Citium too and lovely Λάπηθος.” Πεπάρηθος, an island of the Cyclades, having a city of the same name. Σεσάρηθος, a city of the Taulantini, as Hecataeus says. Κάνηθος, Ὄρηθος, Σέβηθος, the name of a river. ἐπίληθος: “both nepenthes and without gall, making one forgetful of all evils” (Od. δ 221). Ναύαιθος, a river of Italy. Φάρβαιθος, a city of Egypt. Κέλαιθος, a Thesprotian people. Rhianus, book 4: they are also called Κελαιθεῖς. Δάμαιθος; Κύναιθος, one of the sons of Lycaon. Ὀλίγαιθος; Σίμαιθος, the name of a river. Ἀρίαιθος. But βοηθός and κακηθός, ‘the very worst’, are accented on the penult.
Nouns in -θος of more than two syllables, having in the penult two consonants, when not adjectival, are accented on the antepenult: Ἐρύμανθος, a mountain and a river: “either by lofty Taygetus or by Ἐρύμανθος” (Od. ζ 103). Ἄκανθος, a city of Thrace fenced with thorns, whence it has been called, or from some Acanthus, as Mnaseas, book 2, says; there is also in Egypt an Ἄκανθος, book 3; another in the Chersonese near Cnidus, book 4; there is also the one in Athamania. Φάλανθος, a mountain and a city of Arcadia; Pausanias in the eighth book (c. 35, 9) derives it from Φάλανθος. Πύρανθος, a small city or village of Crete near Gortyn. Ψίναφθος, a small town of Egypt, as Alexander says in the second book of the Egyptian Affairs. Μέλανθος, Λαβύρινθος, Ὑάκυνθος, Λέβινθος, Προβάλινθος.