Ἀμύνασθαι

Thucydides [sc. uses this word] to mean a)mei/besqai ["to requite"]¹, but Simonides [uses it] to mean to return favours,² and Sophocles to mean a)palech=sai ["to ward off"].³
The orators apply the [word] a)mu/nasqai to those who have been victims of a prior wrong, when they suffer some evil and do something in return against those who did it first.⁴
Also [sc. attested is] a)mu/nainto ["they might requite"], [the same as] a)mu/naien. Cratinus in Pylaea [writes]: "[he] taught them and he reared them on public funds until they became youths, so that then they might requite destruction."⁵
Also [ac. attested is] a)mu/nein in Thucydides [meaning] to help; but to punish [is] a)mu/nesqai.⁶