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]
The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D. Copyright (C) 2007 by HarperCollins Publishers. Cite This Source
Idioms and Phrases with double-dutch
Language that cannot be understood, gibberish, as in They might have been speaking double Dutch, for all I understood. This usage dates from the 1870s (an earlier version, however, had it as high Dutch) and is heard less often today than the synonym double talk
A game of jump rope in which players jump over two ropes swung in a crisscross fashion.