1. Bad handwriting.
2. Incorrect spelling.
ETYMOLOGY:From caco- (bad), from Greek kakos (bad) + -graphy (writing). Caco is ultimately from the Indo-European root kakka-/kaka- (to defecate) which also gave us poppycock, cacophony, and cucking stool. Opposites of today's word are calligraphy (beautiful handwriting) and orthography (correct spelling). A related word is cacology.
USAGE:"Before I could think of quitting, my boss enlightened me on the virtues of my handwriting, which was sheer cacography: 'Your writing is in direct competition with the Harappan script that still had the hope of being deciphered in the distant future.'"
Vikram Kumar; Positions Very Vacant; The Hindustan Times (New Delhi, India); Apr 15, 2008.
The emails of a former sub-Dean could only be described as cacography.