When the rope is turned inwards, it is called “double Dutch,” when turned outwards, “French dutch.”
He says the document is in Hebrew, and he has translated it into double Dutch.
A double Dutch Agency circulates a report of a great patriotic concert recently held in Berlin.
Language that cannot be understood, esp overly technical jargon: Plain English will do; cut the double Dutch
[1864+; Dutch, ''German,'' being unintelligible, double Dutch is twice as opaque]