Accentuation rules for nouns and names ending in -νας, -πας, -ρας, -σας with examples (anthroponyms and toponyms)
Τὰ εἰς 'νας' ὁμοίως βαρύνεται, εἰ μὴ εἴη ὑποκοριστικὰ ἢ ἐπὶ σκώμματος, Ἀρτύνας, Ξένας, Πρατίνας, Πίνας, Κάνας. Μηνᾶς μέντοι καὶ Ζηνᾶς ὑποκοριστικά. τὸ δὲ δακνᾶς περισπᾶται, ὅτι ἐπὶ σκώμματος τάσσεται. * Τὰ εἰς 'πας' βαρύνεται, Κάλπας, Πάπας, Σκόπας, Λάμπας, Πάμπας, Λίπας, Εὐρώπας, Κύπας, Ἀγρίππας, Ἀράσπας, Γοργόπας, ἅπας. Τὰ εἰς 'ρας', μὴ ὄντα ὑποκοριστικὰ ἢ συναληλιμμένα ἢ νόμισμα δηλοῦντα βαρύνεται, Θήρας, Ἀθύρας ἐπίνειον καὶ ποταμὸς περὶ Βυζάντιον· Εὐφορίων «ὕδατα δινήεντος ἀμευσάμενος Ἀθύραο». ἔστι δὲ καὶ Σικελίας ποταμὸς Ἀθύρας, ὡς Νυμφόδωρος. Τύρας πόλις καὶ ποταμὸς ἐν τῷ Εὐξείνῳ πόντῳ, ὡς ὁ πολυίστωρ. λέγεται δὲ καὶ Τύρις. Κιβύρας ἀδελφὸς Μαρσύου. Ἄρας αὐτόχθων τις, ἀφ´ οὗ Ἀραντία Πελοποννήσου πόλις. Τάρας πόλις Ἰταλίας καὶ ποταμὸς ὁμώνυμος παρὰ θάλασσαν· ἀρσενικῶς δὲ κατ´ ἀναλογίαν. οὐδὲν γὰρ εἰς 'ρας' θηλυκὸν εὑρίσκεται. τοῦτο δ´ εὕρηται καὶ θηλυκῶς. Κάρας. Λάρας. Πείρας. Καίρρας. Ἱμέρας ποταμός, ὡς Νικάνωρ. Χρυσαόρας ποταμὸς Λυδίας. Φαναγόρας. Πυθαγόρας. Σιμμόρας. Ξεναγόρας. Κύδρας. Κόδρας. Λάμπρας. Πρόφρας. Τεύθρας ὁ Πανδίονος, Τίθρας δῆμος τῆς Αἰγηΐδος φυλῆς, Βάβρας πολίχνιον Αἰολίδος ἐγγὺς Χίου ὁμώνυμον τῷ κτιστῇ. Κοψίφρας. τὸ δὲ Μητρᾶς Ἡρᾶς τετρᾶς βορρᾶς περισπᾶται. τὸ δὲ τετράς τετράδος συστέλλεται. * Τὰ εἰς 'σας' βαρύνεται, εἰ μὴ ἀπὸ συμβεβηκότος εἴη Χρύσας, Βαρβύσας, Κέρσας, Πετίσας, Ἀπέσας ὄρος τῆς Νεμέας ὡς Πίνδαρος
Words ending in -νας are likewise accented with a grave, unless they are diminutives or used in mockery: Ἀρτύνας, Ξένας, Πρατίνας, Πίνας, Κάνας. Μηνᾶς, however, and Ζηνᾶς are diminutives. But δακνᾶς is circumflexed, because it is classed as a term of mockery. * Words ending in -πας are accented with a grave: Κάλπας, Πάπας, Σκόπας, Λάμπας, Πάμπας, Λίπας, Εὐρώπας, Κύπας, Ἀγρίππας, Ἀράσπας, Γοργόπας, ἅπας. Words ending in -ρας, when they are not diminutives or contracted or denoting a coin, are accented with a grave: Θήρας; Ἀθύρας, a harbor and a river near Byzantium; Euphorion: “having drawn water from the eddying Ἀθύρα” . There is also a river of Sicily, Ἀθύρας, as Nymphodorus says. Τύρας, a city and a river in the Euxine Sea, as the polymath says; it is also called Τύρις. Κιβύρας, brother of Marsyas. Ἄρας, some autochthon, from whom comes Ἀραντία, a city of the Peloponnese. Τάρας, a city of Italy and a homonymous river by the sea; masculine, however, by analogy, for nothing ending in -ρας is found to be feminine; yet this has also been found in the feminine. Κάρας. Λάρας. Πείρας. Καίρρας. Ἱμέρας, a river, as Nicanor says. Χρυσαόρας, a river of Lydia. Φαναγόρας. Πυθαγόρας. Σιμμόρας. Ξεναγόρας. Κύδρας. Κόδρας. Λάμπρας. Πρόφρας. Τεύθρας, son of Pandion; Τίθρας, a deme of the Aigeis tribe; Βάβρας, a small town of Aeolis near Chios, bearing the same name as its founder. Κοψίφρας. But Μητρᾶς, Ἡρᾶς, τετρᾶς, βορρᾶς are circumflexed. But τετράς, τετράδος is shortened. * Words ending in -σας are accented with a grave, unless they are derived from an accident: Χρύσας, Βαρβύσας, Κέρσας, Πετίσας, Ἀπέσας, a mountain of Nemea, as Pindar says.