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

tireless \tire"less\, a.
   untiring.
   1913 webster

[2] : WordNet (r) 2.0

tireless
     adj 1: showing sustained enthusiastic action with unflagging
            vitality; "an indefatigable advocate of equal rights";
            "a tireless worker"; "unflagging pursuit of
            excellence" syn: indefatigable, unflagging, unwearying
     2: characterized by hard work and perseverance syn: hardworking,
         industrious, untiring
see also:
indefatigable unflagging unwearying hardworking industrious untiring 

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

88 moby thesaurus words for "tireless":
   active, ardent, assiduous, constant, continuing, determined,
   diligent, dogged, dynamic, enduring, energetic, enthusiastic,
   faithful, fervent, hard, hardworking, immutable, inalterable,
   indefatigable, indomitable, industrious, inexhaustible, insistent,
   invincible, laborious, lasting, lively, loyal, never idle,
   never-tiring, obstinate, patient, patient as job, permanent,
   perseverant, persevering, persistent, persisting, pertinacious,
   plodding, plugging, preoccupied, rapt, relentless, resolute,
   sagging, sedulous, single-minded, sleepless, slogging, spirited,
   stable, staunch, steadfast, steady, strenuous, stubborn, tenacious,
   unabating, unconquerable, undaunted, undeviating, undiscouraged,
   undrooping, unfailing, unfaltering, unflagging, unflinching,
   unintermitting, uninterrupted, unnodding, unrelaxing, unrelenting,
   unremitting, unsleeping, unsparing, unswerving, untiring,
   unwavering, unwearied, unwearying, unwinking, utterly attentive,
   vehement, vigorous, vital, weariless, zealous

Tireless >> T Words
Tireless, definition of term: Tireless
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