What is one part in a mixed drink?

A part in a drink is relative to the other ingredients. For instance, 1 part vodka to 2 parts orange juice means that there should be twice as much orange juice added to the drink as vodka.

For accuracy in measurement, a single container meant for measuring alcohol can be used, such as a jigger or shot glass. Both measure approximately 1 ½ fluid ounces, so using a jigger or a shot glass to measure 1 part vodka and 2 parts orange juice would be 1 shot (1 ½ ounces) of vodka and 2 shots (3 ounces) of orange juice.