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.
His wife, Patricia, rose to fame as a socialite and tireless fundraiser for charitable causes, including AIDS research. Foreign Affairs, 24 June 2025 The regular action there, not to mention tireless pregame work with coach David Macias, allowed Sheets to escape a play off the left-field wall without incident on Saturday. Jeff Sanders, San Diego Union-Tribune, 22 June 2025 Described by insiders as a calm, yet tireless worker, a skilled negotiator, and a respected leader, Loftus was promoted to partner at IAG in 2018. Matt Grobar, Deadline, 18 June 2025 Mike Rowe’s new skilled trades partnership is a logical next step in his tireless advocacy for trades careers. Jim Vinoski, Forbes.com, 18 June 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

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Cite this Entry

“Tireless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tireless. Accessed 29 Jun. 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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