The "art" of ordering a smaller size drink but asking for it in a larger size cup to avoid having to pay the higher price of the larger cup.
Here is a common example of upcupping I see in my days at work.

"I would like to order a 16oz Coffee but in a 20oz cup and fill It to the top with cold milk"(or water or ice)...

Being a "professional barista", (I own a small drive thru espresso stand) I see a lot of upcupping by people trying scam me out of a mere .50 or so.
by TheCoffeeBrake101 January 6, 2016
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