indefatigable

adjective

in·​de·​fat·​i·​ga·​ble ˌin-di-ˈfa-ti-gə-bəl How to pronounce indefatigable (audio)
: incapable of being fatigued : untiring
an indefatigable worker
indefatigability noun
indefatigableness noun
indefatigably adverb

Examples of indefatigable in a Sentence

a person of indefatigable patience an indefatigable laborer who can work from sunrise to sunset
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.
Shortly after the devastation, Montag saw music from her debut album Superficial go viral and find new life (spurred in large part by Pratt’s indefatigable promotional skills) with the help of A-list stars and countless TikTok users. Chris Gardner, HollywoodReporter, 24 July 2025 The indefatigable Curtis Sliwa ran uncontested in the Republican primary. Jill Goldsmith, Deadline, 14 July 2025 But at 83, the indefatigable Beatle is indeed taking another spin around the U.S. with his Got Back tour. Melissa Ruggieri, USA Today, 11 July 2025 The indefatigable former Beatle announced the dates for his first North American swing since 2022 on Thursday morning (July 10), a 19-date tour slated to launch at Acrisure Arena in Palm Desert, CA on Sept. 29. Gil Kaufman, Billboard, 10 July 2025 See All Example Sentences for indefatigable

Word History

Etymology

Middle French, from Latin indefatigabilis, from in- + defatigare to fatigue, from de- + fatigare to fatigue

First Known Use

1608, in the meaning defined above

Time Traveler
The first known use of indefatigable was in 1608

Browse Nearby Words

Cite this Entry

“Indefatigable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/indefatigable. Accessed 27 Jul. 2025.

Kids Definition

indefatigable

adjective
in·​de·​fat·​i·​ga·​ble ˌin-di-ˈfat-i-gə-bəl How to pronounce indefatigable (audio)
: capable of working a long time without tiring : tireless
an indefatigable teacher
indefatigably adverb

More from Merriam-Webster on indefatigable

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