To write or draw something quickly or carelessly. (Cambridge Dictionary)
To write hastily or carelessly without regard to legibility or form. (Merriam – Webster)
To cover with careless or worthless writings or drawings. (Merriam – Webster)
Write or draw (something) carelessly or hurriedly. (Oxford Dictionaries)
If you scribble something, you write it quickly and roughly. (Collins Dictionary)
To scribble means to make meaningless marks or rough drawings using a pencil or pen. (Collins Dictionary)
The Art of Scribbling | by Greg Albert.
”Physician’s writing – to scribble like a chicken with claw”