Source : Webster's Revised Unabridged Dictionary (1913)

Exhaustion \Ex*haus"tion\, n. [Cf. F. exhaustion.]
   1. The act of draining out or draining off; the act of
      emptying completely of the contents.

   2. The state of being exhausted or emptied; the state of
      being deprived of strength or spirits.

   3. (Math.) An ancient geometrical method in which an
      exhaustive process was employed. It was nearly equivalent
      to the modern method of limits.

   Note: The method of exhaustions was applied to great variety
         of propositions, pertaining to rectifications and
         quadratures, now investigated by the calculus.

Source : WordNet®

exhaustion
     n 1: extreme fatigue
     2: serious weakening and loss of energy [syn: {debilitation}, {enervation},
         {enfeeblement}]
     3: the act of exhausting something entirely