indefatigable
Americanadjective
adjective
Other Word Forms
- indefatigability noun
- indefatigableness noun
- indefatigably adverb
Etymology
Origin of indefatigable
1580–90; < Latin indēfatīgābilis untiring, equivalent to in- in- 3 + dēfatīgā ( re ) to tire out ( de-, fatigue ) + -bilis -ble
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
At first, Epstein, an indefatigable social networker, was anxious over whether Tisch liked him or not.
From The Wall Street Journal • Feb. 12, 2026
But an indefatigable Volkanovski's agility and relentless striking eventually wore down his flagging challenger, who was unable to land a knockout in the final round.
From Barron's • Feb. 1, 2026
They deserve our support, as do a slew of writers, such as the indefatigable Heather Cox Richardson and Ruth Ben-Ghiat, who publish via Substack.
From Salon • Jul. 5, 2025
These voters “gravitated to Sinclair by default,” observed Carey McWilliams, that indefatigable chronicler of California politics.
From Los Angeles Times • Jul. 2, 2025
Some design changes arose from Lawrence’s own indefatigable quest for the next big technical advance.
From "Big Science" by Michael Hiltzik
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.