κοῦ
From LSJ
Βίων δύο ἔλεγε διδασκαλίας εἶναι θανάτου, τόν τε πρὸ τοῦ γενέσθαι χρόνον καὶ τὸν ὕπνον → Bion used to say that we have two teachers for death: the time before we were born and sleep | Bion said that there are two rehearsals for death: the time before being born and sleep
English (LSJ)
κου, Ion. for ποῦ, που. κοῦα· ἐνέχυρα, and κουάσαι· ἐνεχυριάσαι, Hsch.; cf. κοῖον, κῷα. κούαγμα· σκῆμα, Id. κούαμα· μέλαν (Lacon.), Id. (fort. κουάνια ( κυάνεα) · μέλανα).
Greek (Liddell-Scott)
κοῦ: κου, Ἰων. ἀντὶ ποῦ, που.