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intractable: P. and V. σκληρός.
savage: P. and V. ἄγριος.
invincible: P. and V. δύσμαχος, ἀνίκητος; see invincible.
unbridled: P. and V. ἀκόλαστος, Ar. and P. ἀκρατής; see unbridled.