ISEE/SSAT Vocabulary Builder›Words›I›indefatigable
ISEE/SSAThard
indefatigable
able to continue working without seeming to tire
Synonyms
- tireless
- unflagging
- untiring
Antonyms
- weary
- flagging
- exhausted
indefatigable in a sentence
The indefatigable researcher spent decades tracking the disease across continents.
An indefatigable advocate, Ruiz continued the campaign long after others had withdrawn.
Where it comes from
From Latin indefatigabilis, meaning 'not able to be wearied.'
Memory hook
IN-DE-FATIGUE-ABLE means 'not able to be fatigued': tireless in effort.
Read it in context
- The Ninth Spring Nature
- The Late Correction Arts
Practice indefatigable in the app