The abbreviation "cc" refers to cubic centimeters or the unit of volume used to measure the amount of air an engine can intake. As gasoline engines use combustion for energy, this figure gives a rough estimate of the engine's power.
To fully burn all of the available fuel, an engine requires 15 times more air than gasoline. To increase the energy output, more fuel must be burned and an even greater volume of air must be available. Thus, by listing an engine's displacement, or the volume of air it can intake, a manufacturer is giving a sense of the amount of fuel it can consume and how much power it can generate.