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tireless

American  
[tahyuhr-lis] / ˈtaɪər lɪs /

adjective

  1. never seeming to tire; not slackening: his tireless efforts.

    a tireless worker;

    his tireless efforts.

    Synonyms:
    unfaltering, hardworking, industrious, unwearied

tireless British  
/ ˈtaɪəlɪs /

adjective

  1. unable to be tired; indefatigable

"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

Other Word Forms

  • tirelessly adverb
  • tirelessness noun

Etymology

Origin of tireless

First recorded in 1585–95; tire 1 + -less

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

He founded an initiative helping charities to raise funds and was "known for his kindness and tireless work in assisting others".

From Barron's

That means attacking, staying on the front foot, being aggressive, relentless and tireless.

From Los Angeles Times

"Today we have a huge sense of relief and achievement reflecting years of tireless effort, but also a sense of vindication for their determination that only a public inquiry would do," he said.

From BBC

“It has been my honor to work with a talented, brave, and tireless group of public servants to ensure that the public knows what its government is doing,” he wrote.

From Los Angeles Times

But in most respects, he was Welty’s tireless enthusiast, even writing to the New Republic to defend her from a blistering review of her novel “Delta Wedding” in 1946.

From The Wall Street Journal