The Collaborative International Dictionary of English v.0.48:

Frazzle \Fraz"zle\, v. t. [imp. & p. p. Frazzled; p. pr. & vb.
   n. Frazzling.] [Cf. G. faseln, and E. fray.]
   To fray; to wear or pull into tatters or tag ends; to tatter;
   -- used literally and figuratively. [Prov. Eng. & U. S.]
   [Webster 1913 Suppl.]

         Her hair was of a reddish gray color, and its frazzled
         and tangled condition suggested that the woman had
         recently passed through a period of extreme excitement.
                                                  --J. C.
                                                  Harris.
   [Webster 1913 Suppl.]

The Collaborative International Dictionary of English v.0.48:

Frazzle \Fraz"zle\, n.
   1. The act or result of frazzling; the condition or quality
      of being frazzled; the tag end; a frayed-out end. [Prov.
      Eng. & U. S.]
      [Webster 1913 Suppl. +PJC]

            My fingers are all scratched to frazzles. --Kipling.
      [Webster 1913 Suppl.]

   2. a state of extreme exhaustion; -- often used in the phrase

   worn to a frazzle. [WordNet sense 1]
      [WordNet 1.5]

            Gordon had sent word to Lee that he "had fought his
            corps to a frazzle."                  --Nicolay &
                                                  Hay (Life of
                                                  Lincoln).
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

frazzle
    n 1: a state of extreme exhaustion; "he was worn to a frazzle"
    v 1: wear away by rubbing; "The friction frayed the sleeve"
         [syn: fray, frazzle]
    2: exhaust physically or emotionally; "She was frazzled after
       the visit of her in-laws"