Your browser does not seem to support JavaScript. As a result, your viewing experience will be diminished, and you have been placed in read-only mode.
Please download a browser that supports JavaScript, or enable it if it's disabled (i.e. NoScript).
relating to the study of water on the earth, for example, where it is and how it is used:
Share your knowledge with the community
Browse our collection of 300,000+ community-written definitions
