When your raging alcoholic relative named Rob pours himself a glass that is 90% Vodka and 10% Water.
Ex:

"Whatcha got there Rob?"
"Some water."
"My God man, this is totally a glass of Vodka!"
"Didn't say it was all water."
"We'll just agree to call this Rob water."
by Derpy Leaf Horse July 28, 2019
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