Accent rules and geographic-name examples for Greek nouns ending in -φις, -χις, and -ις; which forms take oxytone, proparoxytone, and exceptions (cities, islands); examples: Κηφίς, Δελφίς, Κολχίς, Ἀντιοχίς, Trakhis, various Egyptian/Libyan cities; note on accusative -α and perispomenon with -ιν forms.
ἡ διασημοτάτη Αἰγύπτου μητρόπολις. τὸ δὲ Κηφίς ὡς ἐθνικὸν ὀξύνεται, ὡς καὶ Δελφίς. Τὰ εἰς 'φις' ὑπὲρ δύο συλλαβὰς ὀξύνεται, εἰ μὴ κύρια εἴη, ἀσταφίς, κροταφίς, ἐλαφίς. Κερκαφίς· Κερκαφίδες δὲ ἀπὸ Κερκάφου αἱ Ῥόδιαι γυναῖκες. καὶ Ἀκραιφίς λίμνη ὡς ἐθνικά. τὸ δὲ Ὄνουφις ὡς κύριον προπαροξύνεται καὶ Μώμεμφις. Ἡρόδοτος δευτέρᾳ (c. 163). Πάρεμφις· εἰσὶ δὲ πόλεις Αἰγύπτου. Τὰ εἰς 'χις' ὀξύνεται, εἰ μὴ ὀνόματα πόλεων ἢ νήσων εἴη, Κολχίς. Ἀντιοχίς ἡ μήτηρ τοῦ Ἀντιόχου καὶ ἐθνικὸν τῆς πόλεως Ἀντιοχείας καὶ φυλῆς ὄνομα, παννυχίς, Τραχίς πόλις Θεσσαλίας ὑπὸ τὴν Οἴτην ὑπὸ Ἡρακλέους κτισθεῖσα καὶ ὀνομασθεῖσα οὕτως διὰ τὴν τραχύτητα. Δουλιχίς, Ἐρυσιχίς· τὸ δὲ ῥάχις καὶ ἔχις σεσημείωται. τὸ μέντοι Ζοῦχις πόλις Λιβύης περὶ τὴν Σύρτιν. Στράβων ἑπτακαιδεκάτῳ. Τρῆχις πόλις Αἰγύπτου, Βῆχις πόλις Αἰγύπτου ἡ πρότερον Μέτηλις. Βῶγχις πόλις Αἰθιοπίας πρὸς τῷ τρίτῳ καταρράκτῃ. Ξοῦχις πόλις Λιβύης. Ἀρτεμίδωρος. Ἀτάρβηχις πόλις ἐν τῇ Προσωπίτιδι νήσῳ, Τεύωχις πόλις Αἰγυπτία. ἔστι καὶ λιμὴν ὁμώνυμος. Ὕδελχις· ἐπὶ πόλεων καὶ νήσων. Τὰ εἰς 'ις' θηλυκὰ ἐπὶ τέλους ἔχοντα τὸν τόνον καὶ εἰς 'α' ποιοῦντα τὴν αἰτιατικὴν ὀξύνονται, ῥανίς, κρηπίς, κνημίς, ἁψίς. Εἰ δὲ εἰς 'ιν' ἔχουσι τὴν αἰτιατικήν, περισπῶνται, Βενδῖς, Μολῖς, Τοτῖς, Ἀταργατῖς.
The most renowned metropolis of Egypt. But Κηφίς, as an ethnic, is accented on the acute, as also Δελφίς. Words in -φις of more than two syllables are accented on the acute, unless they are proper names: ἀσταφίς, κροταφίς, ἐλαφίς. Κερκαφίς; and Κερκαφίδες are the Rhodian women, from Κερκάφος. And Ἀκραιφίς, a lake, as an ethnic. But Ὄνουφις, as a proper name, is accented with the antepenult acute, and likewise Μώμεμφις. Herodotus, book 2 (c. 163). Πάρεμφις; and they are cities of Egypt. Words in -χις are accented on the acute, unless they are names of cities or islands: Κολχίς. Ἀντιοχίς, the mother of Antiochus, and an ethnic of the city Antioch and the name of a tribe; παννυχίς; Τραχίς, a city of Thessaly under Oeta, founded by Heracles and so named because of its roughness. Δουλιχίς, Ἐρυσιχίς; but ῥάχις and ἔχις are noted as exceptions. And Ζοῦχις, a city of Libya near the Syrtis. Strabo, book 17. Τρῆχις, a city of Egypt; Βῆχις, a city of Egypt, formerly Μέτηλις. Βῶγχις, a city of Ethiopia by the third cataract. Ξοῦχις, a city of Libya. Artemidorus. Ἀτάρβηχις, a city on the island Prosopitis; Τεύωχις, an Egyptian city; there is also a harbor of the same name. Ὕδελχις: in the case of cities and islands. Feminine words in -ις that have the accent on the final syllable and make the accusative in -α are accented on the acute: ῥανίς, κρηπίς, κνημίς, ἁψίς. But if they have the accusative in -ιν, they take the circumflex: Βενδῖς, Μολῖς, Τοτῖς, Ἀταργατῖς.