This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

ad. In a manner that produces illegible results.

In an illegible manner: as, a letter written illegibly.

ad. in an illegible manner

"When I explained with the greatest composure, Bonaparte started up in a violent rage, and poured out a flood of abuse, at the same time scratching his name illegibly at the foot of the statement which he had handed in as protocol."