indefatigable

adjective

ˌin-di-ˈfa-ti-gə-bəl How to pronounce indefatigable (audio)
Definition of indefatigablenext
as in meticulous
showing no signs of weariness even after long hard effort an indefatigable laborer who can work from sunrise to sunset

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

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.
Recent Examples of indefatigable The evening encapsulated many special things about Nelson—including his indefatigable quest to harness music and community to uplift the working class. — Andrew R. Chow, Time, 14 May 2026 The Shark, so named early on for his intensity as basketball coach, dean and indefatigable fundraiser, stepped down from the Columbus presidency in 2018 but assumed his current, and final, role. — Howard Cohen, Miami Herald, 1 June 2026 Harry Styles' stage is a pop playground Styles’ laudable core band – anchored by his longtime drummer, the indefatigable Sarah Jones, who makes tricky beats look simple – was augmented by strings and horns on several tracks, a testament to his ambitious musical aspirations. — Melissa Ruggieri, USA Today, 17 May 2026 And while Tom Loftis might not exactly be an indefatigable optimist like Parks and Rec’s Leslie Knope, he’s driven by a passion for civic improvement — and, of course, a desire to show up Eagleton Martha’s Vineyard. — Keith Phipps, Vulture, 15 June 2026 See All Example Sentences for indefatigable
Recent Examples of Synonyms for indefatigable
  1. meticulous
  2. tireless
  3. relentless
  4. unflagging
  5. conscientious
  6. inexhaustible
  7. vigorous
  8. active
Adjective
  • It is well known that Jefferson kept meticulous weather records over several decades.
    — Marshall Shepherd, Forbes.com, 4 July 2026
  • Licensing calls for meticulous attention to ownership splits, territorial rights, and expiration dates.
    — Faye Bradley, Variety, 2 July 2026
Definition of meticulous
Adjective
  • Based on extensive research and conversations with Ms Lee, her family and others in her circle, Roché’s narrative emphasizes how much faith, patience and tireless effort was required of Lee’s generation just to secure the basic dignities of American citizenship.
    — Rob Salkowitz, Forbes.com, 19 June 2026
  • For those performances, not only did an excitedly tireless Conlon spend an hour before performances in the talks, but afterward, despite operas that lasted five hours or more, he could be found behind the bar at Kendell’s, the theater’s downstairs brasserie, serving drinks.
    — Mark Swed, Los Angeles Times, 18 June 2026
Definition of tireless
Adjective
  • Swiss brand On is rapidly disrupting Nike's long-standing dominance in the global running footwear market, alongside Hoka, by prioritizing relentless innovation over celebrity endorsements.
    — Mark Faithfull, Forbes.com, 1 July 2026
  • The story of America is a story of industry, technical skill, and relentless optimism for what the future holds.
    — Mark Rayfield, Fortune, 1 July 2026
Definition of relentless
Adjective
  • Tristan is the ultramarathon of opera roles, long and punishing, and not many tenors carry it off with such unflagging grace.
    — Justin Davidson, Vulture, 11 Mar. 2026
  • The new press release appears to tout that same unflagging punk ethos.
    — Connie Ogle, Miami Herald, 29 Aug. 2025
Definition of unflagging
Adjective
  • Can its legions drink that much beer and still be conscientious enough to clear away the trash?
    — Sun Sentinel Editorial Board, Sun Sentinel, 25 June 2026
  • Trea Turner was conscientious enough to wait for his double-play partner, Bryson Stott, who had authored one of the finest games of his career.
    — Matt Gelb, New York Times, 24 June 2026
Definition of conscientious
Adjective
  • But the collapse of North Atlantic cod remains a stark reminder that nothing is inexhaustible.
    — Encyclopedia Britannica, Encyclopedia Britannica, 30 June 2026
  • People of this era thought the supply of game in America was inexhaustible.
    — Literary Hub, Literary Hub, 10 June 2026
Definition of inexhaustible
Adjective
  • Dunlap notes that borage can grow to about 2 to 3 feet tall and wide, while tomatoes are known for their vigorous growth.
    — SJ McShane, Martha Stewart, 30 June 2026
  • Levine Cava gave the golden-colored dog a vigorous pat on the head.
    — Devoun Cetoute, Miami Herald, 27 June 2026
Definition of vigorous
Adjective
  • People should not approach wild animals that appear sick, injured, or dead, including nocturnal species such as bats and raccoons that are active during daylight hours.
    — Kelli Arseneau, USA Today, 1 July 2026
  • The union has been in active negotiations with the state to draft a new contract, but the two parties had not reached a deal as of Tuesday, when the existing agreement is scheduled to expire.
    — William Melhado, Sacbee.com, 1 July 2026
Definition of active

Browse Nearby Words

in deep water
indefatigable
indefatigably
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Cite this Entry

“Indefatigable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/indefatigable. Accessed 7 Jul. 2026.

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Nglish: Translation of indefatigable for Spanish Speakers

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