is the proof half of the alcohol
Alcohol: US measure of the volume of alcohol (ethanol) in an alcohol-water mixture, expressed as 'degree proof' (Â° proof). One degree proof equals one-half of a percentage. Thus, '80 proof' means 40 percent alcohol, and '200Â° proof' means 100 percent alcohol. 3. Law: Evidence on which the determination of the judgment of a court case is based.