[1] : The Collaborative International Dictionary of English v.0.48

indomitable \indom"itable\, a. l. indomitabilis; pref. in-
   not + domitare, intens. fr. domare to tame. see tame.
   not to be subdued; untamable; invincible; as, an indomitable
   will, courage, animal.
   1913 webster
see also:
tame 

[2] : WordNet (r) 2.0

indomitable
     adj : impossible to subdue syn: never-say-die, unsubduable
see also:
never-say-die unsubduable 

[3] : Moby Thesaurus II by Grady Ward, 1.0

124 moby thesaurus words for "indomitable":
   assiduous, beyond control, brave, breachy, constant, continuing,
   contumacious, courageous, dauntless, defiant, determined, diligent,
   dogged, enduring, faithful, fearless, fractious, immutable,
   impassable, impenetrable, impregnable, inalterable, incontestable,
   incorrigible, indefatigable, indocile, industrious, inexpugnable,
   insistent, insuperable, insuppressible, insurmountable,
   intractable, intrepid, invincible, inviolable, invulnerable,
   irrepressible, irresistible, lasting, loyal, mettlesome,
   never-tiring, obstinate, obstreperous, out of hand, overpowering,
   overwhelming, patient, patient as job, permanent, perseverant,
   persevering, persistent, persisting, pertinacious, plodding,
   plucky, plugging, preoccupied, rapt, recalcitrant, refractory,
   relentless, resistant, resisting, resistless, resolute, resolved,
   restive, sedulous, shrewish, single-minded, sleepless, slogging,
   stable, staunch, steadfast, steady, stubborn, tenacious, tireless,
   unabating, unafraid, unassailable, unbeatable, unbiddable,
   unconquerable, uncontrollable, undaunted, undefeatable,
   undisciplined, undiscouraged, undrooping, unfailing, unfaltering,
   unflagging, unflinching, ungovernable, unintermitting,
   uninterrupted, unmalleable, unmanageable, unmoldable, unnodding,
   unrelaxing, unrelenting, unremitting, unruly, unsleeping,
   unstoppable, unsubduable, unsubmissive, unsurmountable, unswerving,
   untiring, unwavering, unwearied, unwearying, unwinking, unyielding,
   utterly attentive, weariless, wild

Indomitable >> I Words
Indomitable, definition of term: Indomitable
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