οὔ

Particle

 * 1) * Demosthenes, On the Crown 18.71
 * ἀλλ᾽ ὁ τὴν Εὔβοιαν ἐκεῖνος σφετεριζόμενος καὶ κατασκευάζων ἐπιτείχισμ᾽ ἐπὶ τὴν Ἀττικήν, καὶ Μεγάροις ἐπιχειρῶν, καὶ καταλαμβάνων Ὠρεόν, καὶ κατασκάπτων Πορθμόν, καὶ καθιστὰς ἐν μὲν Ὠρεῷ Φιλιστίδην τύραννον, ἐν δ᾽ Ἐρετρίᾳ Κλείταρχον, καὶ τὸν Ἑλλήσποντον ὑφ᾽ αὑτῷ ποιούμενος, καὶ Βυζάντιον πολιορκῶν, καὶ πόλεις Ἑλληνίδας τὰς μὲν ἀναιρῶν, εἰς τὰς δὲ τοὺς φυγάδας κατάγων, πότερον ταῦτα ποιῶν ἠδίκει καὶ παρεσπόνδει καὶ ἔλυε τὴν εἰρήνην ἢ οὔ;
 * But that man, annexing Euboea and fortifying it against Attica, attacking Megara, seizing Oreus, and demolishing Porthmus, installing the tyrant Philistides in Oreus and Cleitarchus in Eretria, placing the Hellespont under himself, besieging Byzantium, destroying some Greek cities and recalling exiles into others; in so doing, was he dealing unjustly, breaking treaties, and destroying the peace, or not?
 * But that man, annexing Euboea and fortifying it against Attica, attacking Megara, seizing Oreus, and demolishing Porthmus, installing the tyrant Philistides in Oreus and Cleitarchus in Eretria, placing the Hellespont under himself, besieging Byzantium, destroying some Greek cities and recalling exiles into others; in so doing, was he dealing unjustly, breaking treaties, and destroying the peace, or not?

Usage notes
is an accented form of used before a pausa (or an enclitic); that is, wherever a final acute accent would not shift to a grave accent.

Particle

 * 1) no
 * 2) * New Testament, Matthew 5:37, Translation KJV
 * ἔστω δὲ ὁ λόγος ὑμῶν ναὶ ναί, οὒ οὔ· τὸ δὲ περισσὸν τούτων ἐκ τοῦ πονηροῦ ἐστιν.
 * But let your communication be, Yea, yea; Nay, nay: for whatsoever is more than these cometh of evil.