δύσκληρος
From LSJ
δὶς ἐξαμαρτεῖν ταὐτὸν οὐκ ἀνδρὸς σοφοῦ → a wise man should not keep making the same mistake, a wise man should not repeat the same mistake, doing twice the same mistake is not a wise man's doing, making the same mistake twice does not befit the wise, making the same mistake twice does not belong to a man who is wise, making the same mistake twice does not belong to a wise man, the wise man does not make the same mistake twice, to commit the same sin twice is not a sign of a wise man, it is unwise to err twice
English (LSJ)
δύσκληρον, unlucky, Phryn.PS p.61 B.
Spanish (DGE)
-ον desafortunado Phryn.PS 61.
German (Pape)
[Seite 682] unglücklich im Loosen, B. A. 34.
Greek (Liddell-Scott)
δύσκληρος: -ον, «ἄτυχος», Α. Β. 34.