Undefatigable a. : Indefatigable.

Example:


Taxonomy
Dictionary, Hms indefatigable, Synonyms, ble, adjective, word origin, ty, ness, bly, fatigue, Houghton Mifflin Company, free online English dictionary, dictionary results, pronunciation, free online dictionary, definitions, websters, spelling.

Defination from the web:
Indefatigable - Definition of Indefatigable at Dictionary.com a free online dictionary with pronunciation, synonyms, and translation of Indefatigable. ... [Obsolete French indéfatigable, from Latin indēfatīgābilis : in-, not; see in-1 + dēfatīgāre, to tire out (dē-, intensive pref. ...