A water bottle, or other liquid carrying vessel used exclusively for strong alcoholic beverages, especially for taking to parks and other areas where alcoholic drinks are prohibited. Usually colored, to hide any suspicious looking liquid, may also be clear if used with gin and tonics or other clear drinks with gin or vodka. This concept was invented by someone who didn't want their regular water bottle to smell like raspberry schnapps for a week. This is a proper noun
Let's take our Duke Nasty to the park.
I am having a picnic. I just have to add the vodka to my Duke Nasty.