Alcohol by volume

Alcohol by volume (ABV) is an indication of how much alcohol (expressed as a percentage) is included in an alcoholic beverage. This measurement is assumed as the world standard. Another way of specifying the amount of alcohol is alcoholic proof. An "alcoholic proof" is roughly twice the alcohol by volume (although this does vary in some countries, see main page for more information). In some countries, alcohol by volume is referred to as degrees Gay-Lussac (after the French chemist Joseph Louis Gay-Lussac).
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