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GRE vocabulary

indefatigable

adjectiveHigh-frequency wordMore I words

incapable of being tired out; tireless

Word origin: From Latin fatigare, to tire.

In a sentence

Indefatigable in a sentence

Here are example sentences showing indefatigable in a sentence.

An indefatigable researcher, she worked through the night for weeks on end.

The indefatigable researcher logged another twelve-hour day, undeterred by months of inconclusive results.

Synonyms
tirelessuntiringunflaggingpersistent
Antonyms
Usage & nuance

Using “indefatigable” well

Indefatigable praises someone who cannot be worn out, emphasizing sustained, tireless effort, and contrasts with weary or lethargic.

Common questions

Questions about “indefatigable

Indefatigable (adjective) means incapable of being tired out; tireless
Here is indefatigable used in an example sentence: "An indefatigable researcher, she worked through the night for weeks on end." Another example: "The indefatigable researcher logged another twelve-hour day, undeterred by months of inconclusive results."
Common synonyms for indefatigable include tireless, untiring, unflagging, persistent.
Antonyms of indefatigable include weary, lethargic.
Indefatigable clusters with tireless, untiring, unflagging, and persistent. Its antonyms weary and lethargic mark the contrast.
Yes. Indefatigable is a high-frequency GRE word, so it is worth prioritising as you build your vocabulary.

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