When salt and other minerals are removed from soil or water, it's called desalination. Desalination can make sea water safe to drink.
The term desalination adds the prefix de-, "undo," to salination, "adding salt." The salty heart of the word is saline, "containing or made of salt." The complex process of water desalination involves using electricity or extreme heat, and it's very expensive. Still, many people around the world depend on desalination of ocean water for drinking and watering crops.