indefatigable
in-di-FAT-i-guh-bul
/ˌɪn.dɪˈfæt.ɪ.ɡə.bəl/
Persisting tirelessly; incapable of being fatigued.
Emphasizes extraordinary stamina and inexhaustible vitality over long periods.
The story behind the word. Built from Latin 'in-' (not) + 'de-' (completely) + 'fatigare' (to tire). Literally, someone who cannot be worn down completely. It entered English in the 16th century to describe soldiers and leaders who seemed immune to physical exhaustion.
Word relationships
- untiring: Untiring is simpler and plain English, whereas indefatigable carries literary weight.
- tireless: Tireless is more common in general speech.
- fatigued: Fatigued means exhausted or drained of energy.
- indolent: Indolent means lazy and avoiding effort.
Commonly confused with
- indefeasible: Indefeasible means unable to be lost or revoked (e.g. rights), whereas indefatigable means tireless.
Word family
- indefatigably (adverb): In a tireless manner.
- indefatigability (noun): Inexhaustible stamina.
Collocations
- indefatigable spirit
- indefatigable campaigner
- indefatigable worker
- indefatigable energy
Idioms & expressions
- tireless energy
Example sentences
- "The indefatigable campaigner spent decades advocating for human rights without losing enthusiasm." Humanitarian work
- "Despite late nights and constant travel, the ambassador remained indefatigable." Political history
Memory hook
IN-DE-FATIGUE-able = INcapable of FATIGUE. Incapable of fatigue.
When not to use
Do not apply to brief activities; it describes continuous endurance.
Fun facts
- In George Orwell's 'Animal Farm', the dedicated horse Boxer is described with this exact word.
Related words
Explore more words
dauntless, Tenacious, incorruptible, relentless, incessant, Pertinacious
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