INDEFATIGABLE Synonyms: 72 Similar and Opposite Words

indefatigable

adjective

ˌin-di-ˈfa-ti-gə-bəl

Definition of indefatigable

as in meticulous

showing no signs of weariness even after long hard effort an indefatigable laborer who can work from sunrise to sunset

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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 Doyle, who limped through a medical career before turning to a life of crime fiction at the age of twenty-seven, had studied under Bell in the late 1870s, marveling at the doctor’s careful reasoning and indefatigable intuition. — Dan Piepenbring, Harpers Magazine, 22 Sep. 2026 Horwitz, 81, is now the vice president for alumni relations, indefatigable in that role but no longer embedded daily with the current roster. — Tyler Kepner, New York Times, 10 Sep. 2026 Gloria Steinem, the indefatigable feminist and journalist whose activism revolutionized the personal and professional lives of women, has died. — Elizabeth Chuck, NBC news, 3 Sep. 2026 San Francisco Playhouse is currently presenting the musical, helmed by company artistic director Bill English (with Phaedra Tillery-Boughton credited as associate director) and starring Ella Ruth Francis as the indefatigable dreamer Tracy Turnblad. — Randy McMullen, Mercury News, 27 Aug. 2026 See All Example Sentences for indefatigable

Recent Examples of Synonyms for indefatigable

Adjective

Each one is crafted in the Swiss workshop, taking two years of meticulous work to come to fruition.

— Rachel Cormack, Robb Report, 5 Nov. 2026
This is where many researchers would have ended their work, but meticulous historic records allowed Kendall’s group to date each individual’s dentin issues even more precisely.

— Andrew Paul, Popular Science, 5 Nov. 2026

Definition of meticulous

Adjective

Change came in Senate races across the country, including in South Carolina, where the seat long held by the late senator Lindsey Graham, a tireless opponent of the Iranian regime, was lost by his sister to a Democratic challenger.

— Ishaan Tharoor, New Yorker, 5 Nov. 2026
Tobe Awaka is the only player who has earned Splitter’s complete approval, earning every minute he’s given on the court through tireless effort to claim any and all rebounds during his rotations.

— Julia Poe, Chicago Tribune, 1 Nov. 2026

Definition of tireless

Adjective

While its megacap rivals are currently engaged in a relentless, capital-intensive arms race to outspend one another on infrastructure, Apple's relatively low capex stands out as a testament to its disciplined capital allocation.

— Michael Khouw, CNBC, 2 Nov. 2026
The Storm was relentless in the second half with 10 shots on goal.

— Paul Johnson, Chicago Tribune, 31 Oct. 2026

Definition of relentless

Adjective

All speakers paid tribute to Jack Gross, owner of the new station, for his untiring efforts to bring San Diego its own television station.

— sandiegouniontribune.com, sandiegouniontribune.com, 17 May 2018
Still, Clark's adrenaline and untiring preparation propelled her to a second place finish in Oslo and a third place finish at the Burton US Open the following month.

— Nihal Kolur, SI.com, 30 Oct. 2017

Definition of untiring

Adjective

Once reading time kicked off during a recent meetup, the only sounds from the group were the quiet rustle of pages turning and the conscientious nibbling of snacks and sipping of tea as the cafe continued its bustle.

— Tribune News Service, Baltimore Sun, 22 Oct. 2026
Even if every senator were ethical, conscientious and committed to the public good, the incentives would remain the same.

— Nicholas Jacobs, The Conversation, 19 Oct. 2026

Definition of conscientious

Adjective

The other three actors opposite this lead figure thrive on seemingly inexhaustible energy slipping in and out of dozens of lightning-fast quirky caricatures.

— Christopher Smith, Oc Register, 6 Nov. 2026
Can Brancusi’s ecstatic and inexhaustible simplicity inspire sculptors to reinvent their medium again?

— Michael Brenson, Vogue, 1 Nov. 2026

Definition of inexhaustible

Adjective

While Bass’ campaign mounted a vigorous media outreach effort in English and Spanish, her own attempts to court Latino voters kept backfiring.

— Los Angeles Times, Los Angeles Times, 10 Nov. 2026
However, removing these roses frees up space, reduces fungal disease and makes room for vigorous varieties that bring pure joy.

— Rita Perwich, San Diego Union-Tribune, 7 Nov. 2026

Definition of vigorous

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in deep water

indefatigable

indefatigably

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“Indefatigable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/indefatigable. Accessed 14 Nov. 2026.

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adjective

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