- indefatigable
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[indefatigable 词源字典] - indefatigable: see fatigue
[indefatigable etymology, indefatigable origin, 英语词源] - indefatigable (adj.)
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- 1580s (implied in indefatigably), from French indefatigable (15c.), from Latin indefatigabilis "that cannot be wearied," from in- "not" (see in- (1)) + defatigare "to tire out," from de- "utterly, down, away" + fatigare "to weary" (see fatigue). Blount (1656) has defatigable, which was in use in 17c. Modern use (1948) probably is a jocular back-formation from indefatigable.