tireless

adjective

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

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.
The city of San Francisco is getting safer, thanks to the tireless work of Mayor Daniel Lurie. Jim Cramer, CNBC, 19 Oct. 2025 Sometimes that truth was heroic—his tireless advocacy for Leonard Peltier, or in defense of the Arctic National Wildlife Refuge—and sometimes the truth was less flattering. Literary Hub, 14 Oct. 2025 The fight for justice never ends as Benson and her squad provide a tireless voice for the voiceless. Denise Petski, Deadline, 10 Oct. 2025 Ati Motors’ Mecha represents this pragmatic vision for the future of robotics, which is not a humanoid for exhibition but a capable, tireless system designed to work alongside humans in industrial settings. Kaif Shaikh, Interesting Engineering, 8 Oct. 2025 See All Example Sentences for tireless

Word History

First Known Use

1591, in the meaning defined above

Time Traveler
The first known use of tireless was in 1591

Browse Nearby Words

Cite this Entry

“Tireless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tireless. Accessed 20 Oct. 2025.

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

Last Updated: - Updated example sentences
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