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[tahyuh r-lis] /ˈtaɪər lɪs/
untiring; indefatigable:
a tireless worker.
Origin of tireless
1585-95; tire1 + -less
Related forms
tirelessly, adverb
tirelessness, noun
unwearied, industrious, hardworking, unfaltering. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for tireless
  • Computers are tireless number crunchers and prodigious data repositories.
  • His humour, such as it is, is tireless and inexhaustible.
  • But, whatever blots there may have been upon his honour, he was tireless in industry.
  • But, by a curious irony, neither poverty nor the bottle impaired the tireless industry of the hacks.
  • His tireless wit came to the aid of his inclination, and his deep knowledge of literature made him welcome even among the serious.
  • She has an extraordinary palate but she's even more widely known as a tireless proponent of local, seasonal, and organic food.
  • The market is world cinema's throbbing id, and its tireless hucksterism carries over into the streets.
  • Stella, whose tireless work ethic makes him an omnivore of source materials and images, didn't stop with smoke rings.
  • They're tireless defenders, life-saving rescuers, and even amateur therapists.
  • Horses have been our faithful servants, our tireless comrades, and our loyal friends.
British Dictionary definitions for tireless


unable to be tired; indefatigable
Derived Forms
tirelessly, adverb
tirelessness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for tireless

1590s, "indefatigable," from tire (v.) + -less. From 1862 in the sense "without a tire," from tire (n.). Related: Tirelessly.

Online Etymology Dictionary, © 2010 Douglas Harper
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