tireless

adjective

tire·​less ˈtī(-ə)r-ləs How to pronounce tireless (audio)
Synonyms of tirelessnext
: seemingly incapable of tiring : indefatigable
a tireless worker
tirelessly adverb
tirelessness noun

Synonyms of tireless

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Examples of tireless in a Sentence

She has been a tireless advocate for reform. a tireless advocate for human rights
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Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Stubborn, single-minded and tireless, lionized and controversial, the Los Angeles water boss was 72. — Los Angeles Times, 6 Aug. 2026 His mother Debra insists her son is alive and has led a tireless campaign to bring him home — a campaign that continues to this day. — Max Goldbart, Deadline, 3 Aug. 2026 Key steps include leveraging AI to proactively answer all buyer questions, then building a comprehensive sales page that acts as a tireless salesperson. — Jodie Cook, Forbes.com, 29 July 2026 As well as his dazzling talent, supporters loved the tireless work rate and enthusiasm of their No 7. — James Pearce, New York Times, 22 July 2026 See All Example Sentences for tireless

Word History

First Known Use

1605, in the meaning defined above

Time Traveler
The first known use of tireless was in 1605

Rhymes for tireless

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Browse Nearby Words

tire gage
tireless
tireman
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Cite this Entry

“Tireless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tireless. Accessed 8 Aug. 2026.

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Kids Definition

tireless

adjective
tire·​less ˈtī(ə)r-ləs How to pronounce tireless (audio)
: seeming never to get tired
a tireless worker
tirelessly adverb

More from Merriam-Webster on tireless

Nglish: Translation of tireless for Spanish Speakers

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