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.
实用例句
1. He was indefatigable in his efforts to secure funding for new projects.
他不知疲倦地努力为新项目寻求资金。来自柯林斯例句
2. an indefatigable defender of human rights
不屈不挠的人权捍卫者来自《权威词典》
3. His indefatigable spirit helped him to cope with his illness.
他不屈不挠的精神帮助他对抗病魔。来自辞典例句
4. He was indefatigable in his lectures on the aesthetics of love.
