defatigate

from The Collaborative International Dictionary of English v.0.48

Defatigate \De*fat"i*gate\, v. t. [L. defatigatus, p. p. of
   defatigare; de- + fatigare to weary. See {Fatigue}.]
   To weary or tire out; to fatigue. [R.] --Sir T. Herbert.
   [1913 Webster]