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indefatigable

play
adjective in·de·fat·i·ga·ble \ˌin-di-ˈfa-ti-gə-bəl\

Simple Definition of indefatigable

  • : able to work or continue for a very long time without becoming tired

Source: Merriam-Webster's Learner's Dictionary

Full Definition of indefatigable

  1. :  incapable of being fatigued :  untiring <an indefatigable worker>

indefatigability play \-ˌfa-ti-gə-ˈbi-lə-tē\ noun
indefatigableness play \-ˈfa-ti-gə-bəl-nəs\ noun
indefatigably play \-blē\ adverb

Examples of indefatigable in a sentence

  1. a person of indefatigable patience

  2. <an indefatigable laborer who can work from sunrise to sunset>



Origin of indefatigable

Middle French, from Latin indefatigabilis, from in- + defatigare to fatigue, from de- + fatigare to fatigue


First Known Use: 1608



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