Gobbledegook

Mr Brookes said the writing within the letters was "gobbledegook, gibberish".

The thought of coaches spouting gobbledegook to a young person with brains in their boots is at best disheartening and at worst overly sanitising.

Dumbledore is known to be able to understand Mermish and Gobbledegook (Goblin language) and Parseltongue.

The word gibberish is more commonly applied to informal speech, while gobbledygook (sometimes gobbledegook, gobbledigook or gobbledegoo) is more often applied to writing.