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.
Below is an itinerary custom-built for those with an indefatigable indie spirit. Brad Japhe, Forbes.com, 30 Apr. 2025 My childhood idol, and the indefatigable chronicler of our games (check Partletonsports.com). Nick Canepa, San Diego Union-Tribune, 19 Apr. 2025 Even the indefatigable Benton slowed down in her later years, afflicted with a heart condition. Richard Selcer, Fort Worth Star-Telegram, 12 Apr. 2025 His Weekend Update favorite Willie, meanwhile, makes the concept of smiling through the unthinkable uniquely funny, with Thompson's indefatigable charm buoying us as much as poor Willie himself. Dennis Perkins, EW.com, 16 Feb. 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 4 May. 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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