When the word "water" is considered, people say it is this liquid that people drink and also that it is this chemical known as H2O. Well, actually these two things are not the same. The chemical, would be closest to distilled water and, it is not healthy to drink. The water you drink has traces of all kinds of chemicals like salts in it. This what makes for it to be good to drink. Another use for the word "water" is to indicate a body of water where you can swim, raft or boat on. In essence it is short for open water and as such it can be both salt and fresh water.
It has been said before by many, it is the simple words where "everyone" understands what is ment which are the hardest to define.