retroversum
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
rĕtrōversum, adv., à reculons : Pl. d. Non. 145, 14 || -versus, en sens inverse : Petr. 44, 12.
retrōversum, s. 2. retrōversus.
