An assemblage of items that are loosely related. Generally considered to be nearly random in composition. The items grouped together are often odd, uncommon, greatly varied, and/or represent nearly every conceivable combination imaginable.
I ordered a packet of wildflower seeds. It was a "duke's mixture" of flowering plants. There were 45 different kinds of seeds in it, and the only thing they had in common was that they all bloomed.
Mainly used by teenagers to secretly take alcohol without their parents knowing.
The process is to take up to an inch of liquour from each bottle you have and add them together into one large bottle so that it looks doesn't like some of the alcohol went 'missing'