👉 A barrelful is a unit of volume used in many countries. It is defined as 1,000 cubic centimeters (cc) or 2 liters (l). This means that it can hold an equal amount of liquid as one large container with a capacity of one liter. For example, a barrelful of water would be exactly the same size as a large container containing a gallon of water (which is approximately 8 pints or 16 cups).