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

untiring \untiring\
   see tiring.
see also:
tiring 

[2] : WordNet (r) 2.0

untiring
     adj : characterized by hard work and perseverance syn: hardworking,
            industrious, tireless
see also:
hardworking industrious tireless 

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

90 moby thesaurus words for "untiring":
   assiduous, cartilaginous, chewy, cohesive, constant, continuing,
   coriaceous, dedicated, determined, diligent, dogged, durable,
   enduring, faithful, fibrous, gristly, hard, hardy, immutable,
   inalterable, indefatigable, indomitable, industrious,
   inexhaustible, insistent, invincible, lasting, leatherlike,
   leathery, loyal, never-tiring, obstinate, patient, patient as job,
   permanent, perseverant, persevering, persistent, persisting,
   pertinacious, plodding, plugging, preoccupied, rapt, relentless,
   resistant, resolute, ropy, sedulous, sinewy, single-minded,
   sleepless, slogging, stable, steadfast, steady, stiff, stringy,
   strong, stubborn, tenacious, tireless, tough, tough as leather,
   unabating, unconquerable, undaunted, undiscouraged, undrooping,
   unfailing, unfaltering, unflagging, unflinching, unintermitting,
   uninterrupted, unnodding, unrelaxing, unrelenting, unremitting,
   unsleeping, unswerving, unwavering, unwearied, unwearying,
   unwinking, utterly attentive, vigorous, viscid, weariless, wiry

Untiring >> U Words
Untiring, definition of term: Untiring
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