ἀδιάτροπος

From LSJ

οὐκ ἔστιν οὐδείς, οὐδ' ὁ Μυσῶν ἔσχατος → there is nobody, not even the last of the Mysians | there is nobody, not even the meanest of mankind

Source

Spanish (DGE)

-ον
perseverante, tenaz γνώμη Rom.Mel.38.ιδʹ.5 (var., cf. ἀδιάτρεπτος).