ἀμύνεσθαι
From LSJ
φθείρουσιν ἤθη χρήσθ' ὁμιλίαι κακαί → bad company ruins good habits
Greek > English (Woodhouse Verbs Reversed)
(see also ἀμύνω): repay, act on the defensive, avenge oneself on, beat off, defend oneself against, defend oneself, drive off, make reprisals, make requital, persons, requite with evil, requite, revenge oneself on, reward a person, stand on one's defence, stand on, take vengeance for, ward off from oneself, ward off