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Showing results for indefatigable. Search instead for indefatigabil.
Definitions

indefatigable

[in-di-fat-i-guh-buhl] / ˌɪn dɪˈfæt ɪ gə bəl /
ADJECTIVE
untiring
Synonyms
STRONGEST
assiduous diligent dogged energetic inexhaustible painstaking relentless tireless unflagging unwavering vigorous
WEAK
active bound and determined dead set on determined hell-bent industrious ironclad nose to grindstone patient persevering persistent pertinacious sedulous steadfast stop-at-nothing strenuous unfaltering unflinching unremitting unwearied unwearying
Antonyms
STRONGEST
changing idle inactive indifferent lazy lethargic negligent tired wavering
WEAK
fatigued weary

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.

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

Mr. Dooley is also a discerning and indefatigable researcher.

From The Wall Street Journal • Jan. 21, 2026

Underlings have long marveled at his indefatigable work ethic.

From Los Angeles Times • Oct. 30, 2025

Tony Doherty, chair of the Bloody Sunday Trust, said: "This day is a tribute to the strength of the families, whose indefatigable campaign for justice has made this happen."

From BBC • Sep. 15, 2025

At midday, despite a scorching sun, Granny, seemingly indefatigable, went about with impressive skill trimming the rosebushes as we talked about trees and flowers and how to best cultivate them.

From "Kaffir Boy: An Autobiography" by Mark Mathabane