What does "sour" refer to in cocktail terms?

In cocktail terminology, "sour" specifically refers to a balanced mixture of sour ingredients such as citrus juice, often combined with a spirit and sometimes a sweetener. This combination typically creates a refreshing contrast of flavors in the drink. The classic example of this is the Whiskey Sour, which combines whiskey, lemon juice, and simple syrup. The sour element is crucial for adding brightness and acidity, enhancing the overall flavor profile of the cocktail.

While there are other aspects to consider in cocktail making, such as the method of preparation or garnish type, the term "sour" clearly defines a style of cocktail that emphasizes the harmonious integration of sour flavor components with base spirits. This distinction helps bartenders create cocktails that are both pliable to individual tastes and aligned with traditional recipes.