> > > > > Water is a actually a very good coolant because it has a very high specific heat capacity of 4.2 J/(K g). This is typically twice as large as organic solvents and at least 4-5 times, sometimes more than 10 times larger than most solids (relative to mass). Since the thermal energy or heat is conserved during the transfer, this means that water can reduce the temperature of the material to be cooled by a certain degree, while its own temperature is increasing only by a fraction of that (considering somewhat similar mass).

Alternatively, you can rely on the very high enthalpy of vaporization of water, by using some form of evaporative cooling. Some animals rely on sweating for thermoregulation, while a lot of computer hardware relies on evaporative cooling in the form of heatpipes or vapor chambers.