ζευγνύναι
From LSJ
μὴ κακὸν εὖ ἔρξῃς· σπείρειν ἴσον ἔστ' ἐνὶ πόντῳ → do no good to a bad man; it is like sowing in the sea
Greek > English (Woodhouse Verbs Reversed)
(see also ζεύγνυμι): undergird, undergird a ship, unite in marriage, with a bridge