ἀνταποφαίνω
From LSJ
ἵνα οὖν μηδ' ἐν τούτῳ δῷ αὐτοῖς λαβήν (Photius, Fragments on the Epistle to the Romans 483.26) → so that he doesn't give them even here a handle (= an opportunity for refutation)
English (LSJ)
A show on the other hand, Th.3.38,67.
German (Pape)
[Seite 244] dagegen zeigen, beweisen, Thuc. ἀνταποφῆναι 3, 48; τὴν ἡλικίαν δεινότερα παθοῦσαν 3, 67. – Med., seine Meinung dagegen aussprechen, Clem. Al. γνώμην, wie Ios.