ETYM Latin indomitabilis; pref. in- not + domitare, intens. from domare to tame. Related to Tame.
Impossible to subdue; SYN. never-say-die, unsubduable.
Impossible to repress or control; SYN. uncontrollable.
Fearlessly, unyieldingly
In an uncontrollable manner, in an unrestrainable manner