in·​de·​fat·​i·​ga·​ble | \ ˌin-di-ˈfa-ti-gə-bəl How to pronounce indefatigable (audio) \

Definition of indefatigable

: incapable of being fatigued : untiring an indefatigable worker

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Other Words from indefatigable

indefatigability \ ˌin-​di-​ˌfa-​ti-​gə-​ˈbi-​lə-​tē How to pronounce indefatigable (audio) \ noun
indefatigableness \ ˌin-​di-​ˈfa-​ti-​gə-​bəl-​nəs How to pronounce indefatigable (audio) \ noun
indefatigably \ ˌin-​di-​ˈfa-​ti-​gə-​blē How to pronounce indefatigable (audio) \ 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 Fleming, an indefatigable and inquisitive researcher, wasn’t so sure. Claudia Kalb, Scientific American, "Penicillin Wasn’t Alexander Fleming’s First Major Discovery," 27 Apr. 2021 So Hepa will take another long journey – Hawaii is about 3,500 miles south of Utqiagvik – and start anew at a program that could use his size, intelligence, long-range shooting and indefatigable optimism. Nick Moyle, San Antonio Express-News, "Texas forward Kamaka Hepa transferring to Hawaii," 26 Apr. 2021 Piazzolla was a man of medium stature who carried a Hemingway-sized chip on his shoulder, confident that his talent, honed through indefatigable study and practice, could transcend the boundaries of his craft. Los Angeles Times, "They called him tango’s assassin. But Astor Piazzolla’s musical reboot made him a legend," 15 Apr. 2021 And while not everyone has her nose for legal research or her borderline-photographic memory for statutes, the focused, indefatigable nature of advocacy is replicable. Robin Kaiser-schatzlein, The New Republic, "How Housing Activists Took on Philadelphia and Won," 29 Mar. 2021 The bewildering — and, presumably for many Israelis, exasperating — sense of Groundhog Day can be attributed to the country’s complicated coalition politics and the indefatigable will to power of Prime Minister Benjamin Netanyahu. Washington Post, "As Israel votes again, Palestinians still wait their turn," 23 Mar. 2021 For 10 of her 12 years in nursing, Ellsworth was an indefatigable intensive care nurse. Scottie Andrew, CNN, "Traumatized and tired, nurses are quitting due to the pandemic," 25 Feb. 2021 The greatest contribution of Mishra’s work is its indefatigable insistence that places long considered marginal belong in the foreground of modern political history. Kanishk Tharoor, The New Republic, "Pankaj Mishra’s Reckoning With Liberalism’s Bloody Past," 22 Feb. 2021 Shirley Abrahamson, an indefatigable jurist known for her activist voice and tart dissents who was the first woman on the Wisconsin Supreme Court and later its first female chief justice, died Dec. 19 in Berkeley, California. Richard Sandomir,, "Shirley Abrahamson, trailblazing Wisconsin judge, dies at 87," 16 Jan. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'indefatigable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of indefatigable

1608, in the meaning defined above

History and Etymology for indefatigable

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

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Time Traveler for indefatigable

Time Traveler

The first known use of indefatigable was in 1608

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Statistics for indefatigable

Last Updated

2 May 2021

Cite this Entry

“Indefatigable.” Dictionary, Merriam-Webster, Accessed 12 May. 2021.

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More Definitions for indefatigable



English Language Learners Definition of indefatigable

formal : able to work or continue for a very long time without becoming tired

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