The term 'Cocktail Mixer' refers to a beverage that is used to mix alcoholic drinks. The two crossword solutions for this term are 'SODA' (4 letters) and 'Club SODA' (8 letters). SODA is a carbonated, sweetened beverage that is usually flavored with fruit or other natural flavors. Club SODA is a type of SODA that has added minerals such as sodium bicarbonate, potassium sulfate, and sodium chloride. It is often used as a mixer in cocktails because it adds flavor and helps to balance the sweetness of the drink.