A.not to be taken, impregnable, of strong places or forts, Hdt.1.84, 8.51; “οὐδὲν ἀ. ἀρετῇ” Chor. in Rev.Phil.1.70: not taken, holding out, Th.4.70.
2. metaph., unassailable, convincing, “αἰσθήσεις” Pl.Tht.179c; of persons, “ἀ. ὑπὸ χρημάτων” incorruptible, X.Ages.8.8: c. gen., τῶν Ἀφροδίτης παθῶν Men.Rh.p.416S.
3. of things, unattainable, [D.]61.37.