salinity

adjective

1. of, characteristic of, or containing common salt, or sodium chloride
2. of or containing any of the salts of the alkali metals or magnesium

noun

1. a salt spring, lick, mine, etc.
2. a salt of magnesium or of an alkali metal, often used as a cathartic
3. a saline solution, esp. one that is isotonic, used in medical treatment or biological experiments