ἐπιδιαφθείρω
From LSJ
περὶ οὐδὲν γὰρ οὕτως ὑπάρχει τῶν ἀνθρωπίνων ἔργων βεβαιότης ὡς περὶ τὰς ἐνεργείας τὰς κατ' ἀρετήν → since none of man's functions possess the quality of permanence so fully as the activities in conformity with virtue
English (LSJ)
A destroy, ruin besides, in Pass., Ph. ap. Eus.PE8.14; become corrupt, Gal.8.42.
German (Pape)
[Seite 938] noch dazu verderben, Philo u. a. Sp.