1. The removal of salt from a body of water or a system; especially, the removal of salt from sea water to make it suitable for drinking.
2. The removal of dissolved salts from seawater and in some cases from the brackish waters of inland seas, highly mineralized ground waters; such as, geothermal water that is saturated or strongly impregnated with salt, and municipal waste waters.

The process of desalination includes removal of dissolved salts from sea water and from the salty waters of inland seas, highly mineralized ground waters, and municipal waste waters.

The process of desalinationmakes such otherwise unusable waters fit for human consumption, irrigation, industrial applications, and for other purposes.