Mash bill whiskey is a type of whiskey that is made from a mixture of different grains. The mash bill is the recipe for the whiskey, and it determines the flavor, aroma, and body of the whiskey.
The most common grains used in mash bills are corn, rye, wheat, and barley. Corn is the most commonly used grain, and it gives whiskey its characteristic sweetness. Rye gives whiskey a spicy flavor, wheat gives it a smooth flavor, and barley gives it a malty flavor.