The definition of indefatigable is a person or something that has tireless persistence.(adjective)
Someone who keeps trying and trying to learn a skill and who never gives up is an example of a person who would be described as indefatigable.
See indefatigable in Webster's New World College Dictionary
Origin: MFr indéfatigable < L indefatigabilis < in-, not + defatigare, to tire out, weary: see de- & fatigue
See indefatigable in American Heritage Dictionary 4
Origin: Obsolete French indéfatigable
Origin: , from Latin indēfatīgābilis
Origin: : in-, not; see in-1
Origin: + dēfatīgāre, to tire out (dē-, intensive pref.; see de- + fatīgāre, to weary).
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