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.
Bartel, by far the most tireless promoter of the Beatles connection with southern Illinois, is himself 77. — Christopher Borrelli, Chicago Tribune, 18 Oct. 2026 But the tireless churn of his storytelling, picking up and depositing little clues of what came before, is the mark of an auteur who has barely scratched the surface of his prowess. — Matthew Ritchie, Pitchfork, 15 Oct. 2026 Thank you to all the Filipino artists who remain passionate and tireless in pushing the boundaries of where Filipino music can be taken globally. — Jeff Benjamin, Billboard, 13 Oct. 2026 The rescue dog’s tireless work to serve others has earned him an ASPCA Humane Award. — Kelli Bender, PEOPLE, 2 Oct. 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 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 27 Oct. 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
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