The Collaborative International Dictionary of English v.0.48:

Cacography \Ca*cog`ra*phy\, n. [Gr. kako`s bad + -graphy; cf. F.
   cacographie.]
   Incorrect or bad writing or spelling. --Walpole.
   [1913 Webster]

WordNet (r) 3.0 (2006):

cacography
    n 1: poor handwriting [syn: scribble, scratch, scrawl,
         cacography]