ὄστινος
From LSJ
τὸ ἐμόν γ' ἐμοὶ λέγεις ὄναρ → you are telling me what I know already, you are telling me my own dream
English (LSJ)
η, ον, (ὀστέον) Att. form of ὀστέϊνος (q. v.) acc. to Poll.2.232, Phot., found in Arist.PA692b18 codd., Gal.18(1).237; τὰ ὄστινα
A bone-pipes, ὀστίνοις φυσᾶν Ar.Ach.863 (spoken by a Boeotian).