Scrawl (8)
I believe the answer is:
scribble
'scrawl' is the definition.
(I know that scrawl can be written as scribble)
This is all the clue.
(Other definitions for scribble that I've seen before include "Write illegibly" , "Untidy writing" , "Write hurriedly" , "Write quickly and/or badly" , "Write carelessly" .)