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
Recent Examples on the Web
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.
But perhaps the most impressive thing the seemingly tireless Parton did during her 80 years was donate much of her wealth to impoverished communities. — Donna Vickroy, Chicago Tribune, 28 Aug. 2026 Gunn, who shares a producer credit with Chris DeFaria, operated from sincere adoration for the characters, in particular the tireless protagonist. — Carlos Aguilar, Los Angeles Times, 26 Aug. 2026 The film seeks to celebrate Guillén’s life while honoring the tireless advocacy of her family, whose campaigning inspired lasting legislative change and amplified the voices of military families. — Andreas Wiseman, Deadline, 19 Aug. 2026 Banks, the first saxophonist to receive the prestigious Avery Fisher Award, is a tireless advocate for his instrument in the classical world. — Beth Wood, San Diego Union-Tribune, 16 Aug. 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

See All Rhymes for tireless

Browse Nearby Words

tire iron
tireless
tireman
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Cite this Entry

“Tireless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tireless. Accessed 30 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
Last Updated: - Updated example sentences
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