ξύν (xyn)
ξύν is an Ancient Greek form of σύν, meaning “with, together with (+dat.)”. It is the preposition.
Found 1,754 times in the Ancient Greek texts on Socratos.
Where it is used
Apollonius Rhodius, Argonautica 3.1279: δή ῥα τότε ξὺν δουρὶ καὶ ἀσπίδι βαῖνʼ ἐς ἄεθλον,
Thucydides, History of the Peloponnesian War 3.104.3: ἦν δέ ποτε καὶ τὸ πάλαι μεγάλη ξύνοδος ἐς τὴν Δῆλον τῶν Ἰώνων τε καὶ περικτιόνων νησιωτῶν· ξύν τε γὰρ γυναιξὶ καὶ παισὶν ἐθεώρουν, ὥσπερ νῦν ἐς τὰ Ἐφέσια Ἴωνες, καὶ ἀγὼν ἐποιεῖτο αὐτόθι καὶ γυμνικὸς καὶ μουσικός, χορούς τε ἀνῆγον αἱ πόλεις.
Sophocles, Oedipus at Colonus 1752: χάρις ἡ χθονία ξύνʼ ἀπόκειται,
Source: Socratos (socratos.org), a free reader for Ancient Greek and Latin. Grammar from the Perseus Treebank and Morpheus; dictionary entries from Liddell-Scott-Jones, A Greek-English Lexicon (Perseus Digital Library, CC BY-SA). Counts are from the texts on Socratos.