παρασφήνιον

ἐπ' αὐτὸν ἥκεις τὸν βατῆρα τῆς θύρας → you've come to the crux of the matter, come to the point, hit the nail on the head, you've come to the very threshold of the door, you are come to the very threshold of the door, you've arrived at the truth of the matter

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Full diacritics: παρασφήνιον	Medium diacritics: παρασφήνιον	Low diacritics: παρασφήνιον	Capitals: ΠΑΡΑΣΦΗΝΙΟΝ
Transliteration A: parasphḗnion	Transliteration B: parasphēnion	Transliteration C: parasfinion	Beta Code: parasfh/nion

English (LSJ)

τό,

A side-block for wedging, IG11(2).159 A 38 (Delos, iii B.C.), PCair.Zen.759 (iii B.C.).