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1.
A plastic disposable cup popular for beer pong as well as for making mixed drinks, as the words SOLO on its side can help you eyeball how much of each liquid to put in. Also known as a keg cup, or simply a Solo.
"I need to pick up some solo cups for tonight's party"
by PattyD March 05, 2007
 
2.
is five dollars.........
Can I get a solo cup? That'll be $5.
by d rat October 04, 2007